The world's top protection agent gets a new client: a hitman who came in from the cold. After being on the opposite ends of a bullet for years, they must team up and have only 24 hours to get to The Hague to bring down a murderous dictator.

Sheldon accuses Dr. Sturgis of plagiarism.

George accidentally sends the school librarian to the hospital.

Sheldon sets out to find the perfect neighbors.

Sheldon has a scientific breakthrough at the dentist's office.

Sheldon discovers Mary's been keeping a secret about him.

After graduating high school, Sheldon has a breakdown when he realizes he may not be ready for college. Also, Dale tries to make amends with Meemaw.

Rachel impulsively gives her telephone number to a handsome guy but worries he will call when Ross is there.

Monica fears the worst when she learns Chandler will be spending Christmas in Tulsa working on a deadline with a beautiful co-worker.

Rachel crosses swords with her temporary replacement at the shop. Phoebe wreaks havoc on the set of Joey's soap opera.

Monica invites Rachel's workplace rival to her birthday party. Joey flirts with Emma's new nanny, and Phoebe and Mike take care of a litter of rats.

Monica exults in the applause she receives on karaoke night, unaware that the cheering audience can see through her blouse.

Joey and Phoebe conspire to send Rachel and Ross on disastrous blind dates.

Joey stumbles upon a way to impress a famous actor during an audition. Ross learns the identity of a long-ago mugger, and Chandler accepts an internship at a shoe company.

Both Monica and Chandler secretly approach Joey for a loan. Phoebe invites Mike to move in with her, and Rachel baby-proofs the apartment.

Ross and Chandler trade barbed insults on their alma mater's Web site.

The gang buys scads of lottery tickets for the multimillion-dollar jackpot.

Rachel's visit to a soap opera set inspires her to dream about Joey. Chandler takes Ross on a weekend getaway after Monica cannot take time off from work.

Ross invites an attractive paleontologist to a rooftop Days of Our Lives party being thrown by Joey.

Sheldon becomes jealous when Stuart asks Amy for a date.

Leonard comes face-to-face with his high school bully.

Sheldon gets in trouble with Amy, and it's up to Penny to teach him how to be a better boyfriend. Howard, meanwhile, must come to grips with Bernadette's dislike of children.

Everything might change when Leonard offers Penny a spur of the moment invitation to a romantic dinner for two on the 100th episode of the series.

Leonard and Penny "beta test" their relationship.

Sheldon's selfish demands force Leonard to reconsider their friendship. Meanwhile, Howard tries to pick his astronaut nickname. NASA astronaut Mike Massimino guest stars.

When Sheldon is forced to take a vacation by the university, he goes to work with Amy in her neurobiology lab.

When a corner office at the University opens up, Sheldon must compete for it with his office nemesis, Barry Kripke. Meanwhile, Penny receives an unusual gift from Amy.

Unable to pull off this week's pickleball and coffee shop challenges, the losing Jokers are forced to participate in an overseas game show hosted by special guest Paul Scheer!

The Jokers are dishing out as waiters, and later grilled by news anchor Rosanna Scotto. Finally, the losing Joker is in for a horrific treat with guest star Bruce Campbell!

Q, Sal and Murr pose as cash-grabby waiters and later as embarrassing parents. After, the losing Joker is forced into a far-out focus group punishment with special guest, and so-called Ganja Weasel, Blake Anderson!

Monica and Chandler run into an old acquaintance when they secretly go to a fertility clinic. Ross helps Joey woo the same professor he wants to date.

Monica and Chandler interview unsuspecting candidates, hoping to find the right man to father their baby.

The gang heads to Barbados for a paleontology convention where Ross is the keynote speaker. David prepares to propose to Phoebe, but ex-boyfriend Mike is not yet out of the picture.

The gang heads to Barbados for a paleontology convention where Ross is the keynote speaker; David prepares to propose to Phoebe, but ex-boyfriend Mike is not yet out of the picture.

In Barbados, Monica, Chandler and Phoebe eavesdrop on their friends' passionate encounters. Monica styles her hair to look like a blowfish, and Phoebe and Mike rekindle their romance.

Ross drinks too much alcohol at dinner with Rachel, Joey and Charlie. Frank Jr. cannot cope with his precocious triplets.

Rachel and Joey nervously anticipate their first real date. Monica and Phoebe try to avoid an obnoxious friend with a fake British accent, and Ross emerges from a tanning booth with a two-toned appearance.

An X-rated cake is delivered to Emma's first birthday party.

Rachel convinces her sister to baby-sit over Ross' protests, and Joey writes a letter to an adoption agency on Monica and Chandler's behalf.

When Ross interviews with Charlie's ex-boyfriend for a prized grant, the doctor makes a shocking stipulation.

The most deranged supervillains in the country are plucked out of prison and enlisted by the government as a ragtag intelligence team.

A young woman discovers that the man of her dreams is really a CIA assassin in this action-packed comedy.

While Sheldon volunteers at a local train museum, Missy embarks on a new stage of womanhood, and Georgie discovers his mother's guilty pleasure.

With college in sight, Sheldon is determined to ride his bike without training wheels and has Missy teach him. Meanwhile, Mary and George argue over parenting styles.

Sheldon finds himself in a fierce competition with Paige after their mothers force them to attend Vacation Bible School. Meanwhile, Georgie makes a questionable purchase.

While Mary and George take a trip, Georgie freaks out when his girlfriend thinks she's pregnant. Dale and Meemaw work out their relationship issues with Dungeons and Dragons.

While college orientation does not go as Sheldon planned, Mary is mistaken for a university student and invited to a party.

Sheldon's first day of college is derailed by his new philosophy teacher. Also, Mary and Brenda live vicariously through Missy's first day of middle school.

Monica and Chandler fuss over their apartment as they expect a visit from the adoption worker. Phoebe and Mike opt for a small wedding and donate the extra money to a children's charity.

Monica prepares a Thanksgiving feast for the gang, then becomes enraged when everyone shows up late. Phoebe convinces Rachel to enter Emma in a baby beauty contest.

A prospective birth mother labors under a misconception about Monica and Chandler's respective occupations.

Rachel and Phoebe spot Chandler getting into a vehicle with a mysterious blond woman.

Joey appears as a celebrity contestant on $100,000 Pyramid. Monica and Rachel hire an ungainly stripper for Phoebe's bachelorette party.

A blizzard causes Phoebe and Mike's wedding to spiral out of control. Uptight Monica steps in as her friend's wedding planner, then drives everyone crazy.

Monica and Chandler show Erica the sights but also learn their baby's biological father might be an unsavory character. Joey begs Phoebe to teach him how to speak French before an audition.

Rachel goes to a job interview at a restaurant and winds up sitting next to her current boss. Joey feels abandoned because Monica and Chandler are leaving.

Ross tries to win back Rachel's job with her former fashion employer. Phoebe tries to keep Joey from learning about his agent's death, and Monica and Chandler make a horrifying discovery.

One of the guys becomes offended when Rachel does not give him the same goodbye she gives the others.

The six friends say goodbye and embark on the next chapters of their lives.

The six friends say goodbye and embark on the next chapters of their lives.

The gang celebrates Halloween at Stuart's comic book store. Meanwhile, Leonard and Penny discover a new spark in their relationship when he seduces her with science.

Sheldon's friendship with renowned scientist Stephen Hawking is threatened by a game of "Words with Friends," while Penny secretly enrolls in a class at the local college.

Bernadette pressures Howard to move out of his mother's house, while Sheldon finds himself caught in the middle of a fight between Amy and Wil Wheaton.

Howard and Raj try to solve a mystery about Sheldon.

Sheldon and Howard battle over an assigned parking spot.

Howard bonds with his father-n-law on a fishing trip.

Sheldon unwillingly revisits some Christmas memories during a lively game of Dungeons and Dragons, while Raj joins the girls for ladies night out.

Sheldon is accused of sexual harassment at the University and winds up dragging Leonard, Raj and Howard into the fray.

Leonard's car is stolen when the guys take a road trip to a comic book convention in Bakersfield, dressed as Star Trek characters.

Outraged that he's being forced to work with his university nemesis, Barry Kripke (John Ross Bowie), Sheldon faces a crisis of conscience.

When Sheldon and Leonard fight, it affects Penny and Amy's living arrangements. Meanwhile, Raj takes care of Mrs. Wolowitz while Howard is away.

Sheldon struggles to find a Valentine's gift for Amy.

Raj vows never to leave his apartment after a horrible date.

Leonard, Sheldon and Howard try to advance the cause of women in science by speaking with junior high girls about their future careers, while Raj plans his date with Lucy.

Raj vows never to leave his apartment after a horrible date.

Leonard, Sheldon and Howard try to advance the cause of women in science by speaking with junior high girls about their future careers, while Raj plans his date with Lucy.

Roger is forced to confront himself after a series of accidents. Klaus and Jeff bond.

Steve profiles Stan for an essay contest at school. Francine uses a porta john.

Roger and Steve try to save a dying mall.

Meemaw takes matters into her own hands when Sheldon's philosophy teacher, Professor Ericson, sends him into a tailspin.

Sheldon and his dad dine with President Hagemeyer and a university benefactor. Also, Dale and his ex-wife invite Meemaw to their son's wedding.

Sheldon campaigns to become Dr. Linkletter's lab assistant. Meanwhile, Georgie enlists the help of Mr. Lundy, the drama teacher, for a surprising business venture.

Dr. Linkletter pushes Sheldon to make friends with his fellow students, and Georgie gets a pager.

Sheldon, Dr. Linkletter and Meemaw team up on a science experiment. Also, Mary is jealous that Pastor Jeff and Brenda are spending so much time together.

Sheldon refuses to ride in a car after getting into an accident with Meemaw. Meanwhile, Meemaw is forced to take the church shuttle while her car is in the shop.

After Rachel leaves her fiance at the altar, she moves in with Monica and finds that independence is not so easy, particularly without Daddy's credit cards.

Ross is stunned to learn his ex-wife is pregnant with their child. Monica's dinner for her overly critical parents is a disaster.

The group loves Monica's new boyfriend. Chandler resumes smoking, and Phoebe receives a large sum of money unexpectedly.

While the men attend a hockey game and end up at a hospital, the women spy on President Clinton's top aide, George Stephanopoulos, who lives across the street. Rachel receives her first paycheck.

While Phoebe and Chandler end their respective romantic relationships, Rachel and Ross do laundry together on their first date.

Joey gets a film role as a stand-in for Al Pacino's butt. Ross tries to be less conservative. Chandler has an affair with a married woman.

A citywide power outage leaves Chandler stranded in the vestibule for an automatic banking machine with gorgeous model Jill Connick. Ross tries to ask Rachel out on a date. Joey learns Monica used to be infatuated with him.

When Ross and Monica's grandmother dies, the whole gang attends the funeral service. Chandler questions his sexual persona when a co-worker wants to arrange a date for him with another guy.

Monica intends to host a cozy Thanksgiving feast in her apartment with her friends but her plans go awry, and the feast becomes a fiasco.

The friends promise to celebrate New Year's Eve without dates but soon all their plans change. Ross gets a pet monkey.

Chandler's flamboyant mother comes to New York for a visit. Phoebe and Monica cause a traffic accident.

Rachel's Italian boyfriend tries to seduce Phoebe. Rachel accidentally reveals a secret to Ross. Monica's aunt refuses to take the lasagnas she ordered from Monica.

Raj vows never to leave his apartment after a horrible date.

Leonard, Sheldon and Howard try to advance the cause of women in science by speaking with junior high girls about their future careers, while Raj plans his date with Lucy.

To open or not to open? When Howard finds a letter from his father, he's forced to confront his past. And Leonard and Penny throw a grown-up cocktail party at the apartment.

Leonard, Sheldon and Raj fight for tenure at the University.

After one of his favorite TV shows gets canceled too soon, Sheldon feels lost, so Amy tries to help him get over his compulsive need for closure by retraining his brain.

Leonard and Sheldon hire Professor Proton (Bob Newhart), the host of their favorite childhood TV show to perform. Raj leaves his dog with Howard and Bernadette.

Stan is forced to co-lead a scouts troop with Hayley while Steve blunders in his fantasy world.

Jeff's people-pleasing nature gets in the way of his relationship with Hayley. Stan wears a confusing costume to the CIA costume party.

When Francine successfully grows a garden, it reminds Roger he knows a recipe for truly authentic jambalaya.

Hoping to teach him the value of sharing, the family recreates a television show from Klaus' childhood. Roger has a piano recital.

When the IRS accuses Sheldon of making a mistake, he stops at nothing to prove them wrong. Then, when Dale is forced to get a colonoscopy, he tries to convince Meemaw to join him.

Sheldon faces extreme consequences after installing a pirated computer game. Meanwhile, Mary and Meemaw take Brenda out for Girls Night, while George watches Billy.

Sheldon finds himself at odds with Paige once again when she considers enrolling at East Texas Tech. Meanwhile, Mary seeks the advice of June when looking for a change.

The Coopers discuss the possibilities of black holes and alternate universes when Dr. Sturgis comes over for dinner.

In the fourth season finale, Missy's first heartbreak triggers a series of events that lead the Cooper family to the brink.

In the fifth season premiere episode, Sheldon and Missy both run away from home, while Mary gets some upsetting news about her husband, George.

Chandler sees Rachel nude. Joey learns his father is having an affair.

On Valentine's Day, Ross meets his ex-wife while on his first date in nine years. The girls rebel by burning mementos of past relationships.

A restaurant owner interviews Monica for a chef's position. Ross asks Joey how to talk dirty to women.

Phoebe's twin sister causes confusion and conflict. Ross attends childbirth classes with his ex-wife and her girlfriend.

Rachel and Monica squabble over two handsome doctors. Ross ponders his impending fatherhood with his own father.

The women lose money in a poker game with the men. After getting advice from a champion card player, they demand a rematch.

Rachel accidentally lets Ross' pet monkey escape, and the friends form a search party. Rachel learns that her former best friend is engaged to marry Rachel's former fianc?.

Rachel reunites with her duplicitous ex-fiance. Chandler agonizes about a woman who doesn't call him after the first date.

Monica meets a woman who helps her live out her fantasies. Ross' pet monkey becomes sexually mature and makes everyone crazy.

Monica finds out more than she wants to know about her latest love. Chandler's friends at work treat him differently since his promotion. Ross' ex-wife begins giving birth.

When Carol gives birth, Ross and Susan almost miss the event. Joey befriends an unmarried pregnant woman.

Rachel finds out about Ross' secret love for her but another surprise awaits her.

When the girls' trip to Vegas falls through, the guys invite them to a Dungeons & Dragons date night that causes Sheldon and Amy's relationship to take an unexpected turn.

On the sixth season finale, Sheldon and Penny are thrown for a loop when Leonard is offered an exciting new job opportunity overseas.

Leonard is away at sea, so Sheldon and Penny spend time together and spill some revealing secrets. Meanwhile, Howard comes to Raj's aid after his breakup with his girlfriend.

Leonard returns from the North Sea expedition and finds things chilly between him and Sheldon, while Howard's relationship with his mother opens the door to questions about his masculinity.

Raj puts together a scavenger hunt that turns into serious, cutthroat competition among the gang.

Sheldon is fit to be tied when Amy ruins one of his favorite adventure films, while Leonard finds the key to getting Penny to do his bidding, and Raj and Stuart get creative with their online-dating profiles.

Amy takes a job at Sheldon's university, putting their relationship to the test.

Sheldon makes a major scientific breakthrough, but he feels it may haunt him for the rest of his career. Meanwhile, Howard makes a grand romantic gesture to Bernadette, which causes Penny to put more effort into her relationship with Leonard.

The gang celebrates Halloween at Stuart's comic book store. Meanwhile, Leonard and Penny discover a new spark in their relationship when he seduces her with science.

Sheldon's friendship with renowned scientist Stephen Hawking is threatened by a game of "Words with Friends," while Penny secretly enrolls in a class at the local college.

Bernadette pressures Howard to move out of his mother's house, while Sheldon finds himself caught in the middle of a fight between Amy and Wil Wheaton.

Howard and Raj try to solve a mystery about Sheldon.

Sheldon encourages Missy to question the Bible. Also, Meemaw is determined to catch George Sr. in a lie, and Mary helps Pastor Jeff search for a youth pastor.

While Sheldon tries to convince Dr. Sturgis to return to the university, Georgie upsets the family when he makes a life-changing decision.

While Meemaw opens a secret gambling room, Sheldon, Missy and Georgie adapt to new living arrangements.

While Mary's away, George finds himself giving advice on Missy's love life. And Georgie has a solution for Meemaw's business woes.

Missy asks some uncomfortable questions about sex in church.

Sheldon takes his first engineering class with Professor Boucher. Also, Meemaw and Dale help take care of his ex-wife, June.

Rachel gets an unpleasant surprise when Ross returns home. Phoebe has varied success cutting the friends' hair.

Phoebe unwittingly disgusts everybody. Joey competes with a fellow salesman.

The downstairs neighbor dies and bequeaths his strange possessions to Monica and Rachel.

Everyone is surprised when Phoebe's husband shows up.

The friends want to give Ross a birthday party but disagree about money. Monica gets promoted and learns a tough lesson.

Joey and Chandler try to attract women with baby Ben. Phoebe gets terminated from her singing job and replaced by a professional, Stephanie.

Dramatic developments occur in Ross and Rachel's relationship. Chandler regrets asking Monica to help him lose weight.

Rachel makes a painful discovery concerning Ross. Monica's new boss gives her an impossible task.

Phoebe learns the surprising truth about her father. Ross makes Monica's Christmas party guests miserable.

Joey gets a great acting opportunity. Rachel dates a guy who is amazingly similar to Ross.

Carol and Susan prepare for their wedding with some help from an uncomfortable Ross.

Ross searches for his former pet monkey. Joey dates an obsessed fan.

When Sheldon's childhood hero, Professor Proton, seeks Leonard's help with an experiment, the slighted Sheldon goes nuclear and decides to get revenge by befriending another TV science guy.

Leonard fails to stop Sheldon from overreacting after a past slight comes to light, and as punishment Leonard must walk a mile in Sheldon's shoes. Meanwhile, Penny has a run-in with Raj's former girlfriend Lucy.

Howard's mother has a say when he and Bernadette host Thanksgiving dinner for the gang.

When Sheldon's accidental scientific discovery is disproved, Amy and Leonard try to help him deal with the shame and the disappointment. Meanwhile, Howard and Bernadette open their home to Raj for a week.

With Sheldon in Texas, the gang gathers to decorate for Christmas, and they each contemplate if they would have had a wonderful life had they never met him.

Things turn rocky between Sheldon and Wolowitz after a barrage of insults, and Bernadette steps in to mediate a peace. Meanwhile, Penny is offered a movie role that may prove embarrassing.

Billy Batson is a streetwise 14-year-old who can magically transform into the adult superhero Shazam simply by shouting out one word. His newfound powers soon get put to the test when he squares off against the evil Dr. Thaddeus Sivana.

While Sheldon battles the mysterious Grand Chancellor of the university over science requirements, Mary discovers that Georgie is working at Meemaw's illegal gambling room.

While George Sr. plays handyman at Brenda Sparks' house, Sheldon gets the science yips and has to learn how not to think.

Sheldon gets a dorm room all to himself, which soon becomes the campus hotspot. Meanwhile, Meemaw gets an unwanted business partner.

Sheldon acts as Mary's spy when he's forced to spend the night at church for a youth lock-in. Meanwhile, Georgie finds himself attracted to an older woman.

Sheldon attends his first comic book convention, and Mary tries selling make-up.

When a new scientist joins the lab, Sheldon is the odd man out. Meanwhile, Mary is given a lotto ticket.

Ross spends some quality time with Marcel, his former pet monkey. Chandler gets a big surprise from a sexy former classmate.

Monica's old home video shows Ross' true feelings for Rachel. Joey gives a gaudy gift to Chandler.

Ross and Rachel encounter obstacles to romance. Monica becomes enamored with a handsome, older doctor.

Monica's parents find out about her middle-aged boyfriend. Chandler and Joey argue and it could mean the end of their living arrangement.

Joey wants to move back in with Chandler, but there's a new problem. Phoebe tapes a rock video. Ross upsets Monica.

Monica and Richard experience the same romantic problems as Rachel and Ross. Joey's ill-advised comments to a fan magazine threaten his acting career.

Chandler wants his annoying new roommate to move out. Joey's exorbitant bills come due. The women learn from a book about personal empowerment.

Monica's boyfriend impresses Chandler and Joey. Phoebe finds out what she missed as a child.

Two bullies eject Chandler and Ross from Central Perk. Phoebe meets a brother she never knew she had.

Rachel gets a surprise at her birthday party when her parents show up.

When Phoebe catches chickenpox, her chances for romance with a former lover are almost ruined. Monica worries that she is too strange for Richard.

Rachel is a bridesmaid at her ex-fianc?'s wedding. Monica and Richard's relationship is jeopardized when the subject of children is discussed.

Penny turns to Leonard for comfort after her guest appearance on NCIS does not turn out well. She ends up putting Leonard on the spot regarding their relationship. Sheldon works on his sense of humor, and Raj practices talking to girls.

There's impactful news on the work front as Penny makes a big step toward pursuing a full-time acting career, and Sheldon is forced to take a vacation.

Unable to score tickets for Comic-Con, Sheldon decides to stage his own comic-book convention, while the ladies attempt to act like grown ups.

Amy has amour on her mind when she talks Sheldon into a romantic Valentine's Day getaway to Napa Valley wine country. Back at home, Leonard and Penny make an emergency visit to the vet with Raj's dog.

Leonard's purchase of a dining-room table for the apartment doesn't sit well with Sheldon, so much so that it forces him to reevaluate his life. Meanwhile, Bernadette isn't quite over the moon about Howard taking another trip to space.

While Sheldon and Howard continue their bonding, Sheldon's visit to see his mommy forces him to start addressing a new reality. The gang are subjected to a murder mystery party that leads them to speculate where they might be in 20 years.

Raj wrestles with dating two women at the same time, Penny is offered a part in a trashy movie, and Sheldon can't decide between two gaming systems.

After his father goes missing, Tim joins forces with his dad's partner, Detective Pikachu, to unravel the mystery, and, in the process, uncovers a plot that could destroy the peaceful co-existence between humans and Pokémon.

Ross' secret fantasy doesn't stay secret for long after he confides in Rachel. Chandler resumes an old relationship.

Ross becomes frantic trying to get everyone ready to leave to hear his speech at the museum.

Monica wants to have a baby. A man is stalking Phoebe.

Chandler wants to commit to a relationship with Janice. Phoebe poses as Joey's agent.

Phoebe tries to be more friendly with her half-brother. Ross meets Isabella Rossellini.

The friends recall secrets from their pasts.

Raj and Howard double-date, and the latter is flushed with embarrassment after Raj's girlfriend reveals a secret she knows about Howard.

Leonard reinstates Anything Can Happen Thursday, and it leads the regimented Sheldon to attempt something spontaneous, which creates friction among Penny, Amy and Bernadette. Raj requests help from Howard in prepping for a date with Emily.

Sheldon receives counseling from his childhood TV idol, Professor Proton, while Penny and Leonard reach a relationship milestone and turn it into a competition. Also, Bernadette and Amy turn Star Wars Day into a special event for the guys.

A trying day at the movie shoot leaves Penny with questions about her life choices, so she decides to act on it. Caring for a bedridden Mrs. Wolowitz proves a challenge for Howard and Bernadette.

Fast-forward to the 1980s as Wonder Woman's next big screen adventure finds her riding lightning across the sky, donning wings of gold and chasing a dream while in pursuit of two new formidable foes.

Joey sees Janice kissing her husband, whom she is divorcing while she dates Chandler. Rachel's father clashes with Ross.

Chandler and Janice make a difficult decision about their relationship. Monica accidentally injures Ben and tries to hide it from Ross.

On Thanksgiving, a good-natured football game between the friends reveals some serious rivalries.

Rachel wonders if she'll ever get another job after she quits Central Perk. Joey's new job selling Christmas trees upsets Phoebe. Ross breaks a little girl's leg.

Fortified in a massive, armored truck, loner Mad Max joins Imperator Furiosa and her band of rebels as they try to outrun a warlord and his henchmen in a deadly high-speed chase through the Wasteland.

Aquaman must retrieve the legendary Trident of Atlan to save the underwater city of Atlantis -- and the surface world -- from his power-hungry brother.

Fast-forward to the 1980s as Wonder Woman's next big screen adventure finds her riding lightning across the sky, donning wings of gold and chasing a dream while in pursuit of two new formidable foes.

After a terrible accident, Dr. Stephen Strange loses his ability to operate but finds new purpose when a mystical being known as the Ancient One reveals that Dr. Strange is the newly designated Sorcerer Supreme.

Aquaman must retrieve the legendary Trident of Atlan to save the underwater city of Atlantis -- and the surface world -- from his power-hungry brother.

Sheldon makes friends with his dorm neighbors. Meanwhile, George Sr. learns his job is in jeopardy.

Sheldon joins Dr. Linkletter and Dr. Sturgis on a science road trip, which lands them in the middle of nowhere. Meanwhile, Georgie continues to lie about his age.

When Meemaw's gambling room is a success, she finds herself with a suitcase of illegal cash. Meanwhile, Missy starts a business and Sheldon dips his toe in the stock market.

In the 100th episode, Sheldon gets an odd request from an old friend, while George and Mary are caught in the middle of Meemaw and Dale's breakup, and Georgie comes clean to Mandy.

While Sheldon copes with the death of a hero, Georgie struggles with his big secret, and Missy wants to babysit.

George and Mary insist on meeting the new woman in Georgie's life, while Sheldon and Missy have suspicions about what's going on with their family.

Rachel meets a handsome stranger, who might help her career. Chandler gets into trouble with Joey's sisters.

Ross overreacts when Rachel starts working with a handsome guy. Monica becomes enamored with a sexy busboy.

When Monica and Richard accidentally meet, they decide to become friends with dire consequences.

Phoebe's ex-singing partner wants to make Phoebe's signature song, Smelly Cat, a commercial success. Chandler dates a woman with a handicap.

Phoebe becomes involved with a foreign diplomat. Ross becomes involved with another woman after a fight with Rachel.

Ross wakes up with Chloe but an oblivious Rachel wants to resume their relationship.

Ross and Rachel remain apart while their friends feel forced to choose between them.

Phoebe is distraught when her brother wants to marry a woman twice his age. While working as a waitress, Monica gets a tip from an admirer worth a small fortune. A hypnosis tape makes Chandler act like a woman.

Ross is upset when Rachel returns his personal belongings and dates Mark. Monica dates a millionaire.

Joey thinks he's found his true love. Rachel's boss dates Chandler, creating big trouble for Rachel. Monica inherits a dollhouse.

When Pete buys a restaurant, Monica must make a difficult decision. Ross makes a sacrifice for Rachel. Joey buys Chandler an unusual pet.

Ross tries to convince Rachel that her date is psychotic. Joey's play gets terrible reviews.

Sheldon gets caught up in all the life-altering changes going on around him and considers a monumental move.

Amy and Leonard take a surprise road trip to Arizona, while Penny goes on a job interview at Bernadette's company, and Howard has problems wrapping his head around Stuart's relationship with Mrs. Wolowitz.

Sheldon wants to use an alternate version of rock-paper-scissors to help resolve conflicts. A girl Wolowitz has a major crush on falls for Leonard.

Leonard and Raj take Wolowitz to Las Vegas to help him get over his break-up with Leslie. Sheldon, home alone and looking forward to it, locks himself out and has only one other place to stay: Penny's.

Discovering Leonard, Raj and Howard fudged the results of his Arctic research expedition, a disgraced Sheldon heads home to Texas.

An appearance in traffic court comes at the worst possible time for Sheldon, the same day Stan Lee is appearing at the comic book store.

The guys camp out in line to see a print of Raiders of the Lost Ark with 21 extra seconds and are outraged to see Wil Wheaton and his friends being allowed to skip the line. Penny and Bernadette invite Amy to their girls night.

Sheldon chooses to participate in a guys-only weekend Star Wars gaming marathon rather than go with Amy to her aunt's birthday party -- and gets a lesson from Penny and Amy.

The gang celebrates Halloween at Stuart's comic book store. Meanwhile, Leonard and Penny discover a new spark in their relationship when he seduces her with science.

Unable to score tickets for Comic-Con, Sheldon decides to stage his own comic-book convention, while the ladies attempt to act like grown ups.

Sheldon receives counseling from his childhood TV idol, Professor Proton, while Penny and Leonard reach a relationship milestone and turn it into a competition. Also, Bernadette and Amy turn Star Wars Day into a special event for the guys.

Professor Proton visits Sheldon in a dream and gives him Obi-Wan Kenobi-like advice about whether to go see the new "Star Wars" film or spend the time with newly reunited girlfriend Amy on her birthday.

Amy and Leonard take a surprise road trip to Arizona, while Penny goes on a job interview at Bernadette's company, and Howard has problems wrapping his head around Stuart's relationship with Mrs. Wolowitz.

Sheldon is ordered to teach a class, and the gang is surprised when Howard signs up to take it, and tensions between Penny and Bernadette afford Amy an opportunity to play one against the other.

Murr and Q are going on a trip down memory lane and watching extended never-been-seen-before clips from the last few years.

Despite the whole family trying to keep it a secret, Sheldon and Missy learn about Georgie's pregnancy.

With the Coopers facing judgement from the congregation in the wake of Georgie's pregnancy, Sheldon is distracted by the family drama, while Missy stands up for her brother.

Sheldon struggles with the first signs of puberty while his parents both hunt for new jobs, and Georgie and Meemaw take a business trip across the border.

George Sr. bails Meemaw and Georgie out of jail. Also, Sheldon and Missy meet Mandy, and Mary feels unwelcome at church.

Sheldon and Missy try to help the family's finances. Also, Mary struggles to find her footing without the church.

Sheldon must choose sides in an ethical dilemma. Mary tries her hand at writing. Mandy needs a new place to live.

Ross finds a strange growth on his buttocks. Phoebe can't choose between two guys. Monica's boyfriend surprises her.

Monica's boyfriend cannot stop fighting. Chandler's boss is overly friendly.

The friends stay at a beach house. Phoebe meets someone who knows details about her family. Rachel expresses her jealousy of Ross' uninhibited girlfriend.

Ross loves dating Rachel again but hates what he did to accomplish the reconciliation. Phoebe gets to know her mother.

Phoebe thinks her adoptive mother's spirit inhabits a stray cat. Joey's attempt to sell his entertainment center proves hazardous.

Monica tries to prove her mother wrong. Chandler gets into an embarrassing situation while dating Rachel's boss.

Joey makes an odd deal with the building superintendent to prevent him from evicting Rachel and Monica. Phoebe wants to date her sexy massage client.

Joey thinks Chandler hates Joey's new girlfriend -- but the truth could be even more upsetting. Ross and Rachel try to make each other jealous.

Ross' beautiful new girlfriend has a disgusting secret. Chandler becomes more familiar with Joey's girlfriend.

Chandler is guilt-ridden after kissing Joey's girlfriend. Ross' musical talents are not as amazing as he and Phoebe think.

On Thanksgiving, Joey wants to punish Chandler for kissing Kathy. Monica gets a surprise when she visits an eye doctor.

The guys try to be spontaneous and wild. After Monica gives a bad restaurant review, she receives a new career opportunity. Rachel's boss offers her a promotion.

Sheldon is ordered to teach a class, and the gang is surprised when Howard signs up to take it, and tensions between Penny and Bernadette afford Amy an opportunity to play one against the other.

A nervous Wolowitz is thrown for a loop when NASA asks him to toss out the first pitch at a Los Angeles Angels baseball game. Meanwhile, Sheldon brags that he and Amy are a better couple than Leonard and Penny.

Raj's girlfriend, Emily, gives Penny the cold shoulder after he reveals some info about their past history; and the guys contemplate buying into Stuart's comic-book emporium.

Amy and Bernadette accuse former party girl Penny of becoming a party pooper when she lets an email from work impact their girls' weekend in Las Vegas. Meanwhile, the guys brainstorm about inventing something cool.

Sheldon and Raj undertake an underground research expedition that turns into a test of how long before they get under each other's skin. Meanwhile, Leonard and Penny argue about money.

Hayley tries to help Roger write a book.

A lunar misstep sends Roger on an unexpected detour to New Mexico.

Steve and Principal Lewis get caught in a dangerous situation at the school, while the rest of the family makes an adorable new friend.

Klaus and Jeff's friendship is threatened by Klaus's girlfriend from another realm.

When Jeff finds out that the family thinks he makes terrible decisions, he decides to take a job selling stretchy leggings to prove them wrong.

Francine insists that Steve let her help with his school project, Stan finally fixes that shingle, and the rest of the family goes on a quest to return Gallagher's mallet.

It's Halloween night, and Stan is missing, so the Smith gang heads to the spooky, abandoned CIA headquarters to investigate.

The judgmental voice in Hayley's head makes it impossible for her to enjoy a girls' night with Nerfer and Danuta.

When Steve gives the family better Christmas gifts than Stan, Stan goes to great lengths to regain his title of "King of Presents."

When Stan discovers anonymous love letters written to Francine, he worries that this secret admirer could threaten their relationship.

Murr, Q and Sal will be sitting alongside a stranger to participate in a documentary-style interview. Then, they'll be trying to upcharge guests again as hotel concierge. At the end, one of them will be working up a sweat as Peloton's biggest nightmare.

Sheldon makes a terrifying mathematical discovery while tutoring Billy. Also, Mary is jealous of Missy's relationship with Mandy and MeeMaw.

Sheldon becomes a dorm RA. Meemaw and Dale make a sketchy business deal. Mary and George Sr. rekindle their romance.

Sheldon's search for a comic book leads him to a breakthrough. Also, Georgie and Mandy have an uncomfortable first encounter with her parents, Jim and Audrey.

Sheldon's database invention puts him at odds with the university. Also, the church takes issue with Meemaw's video store.

Sheldon considers dropping out of college to focus on building his database. Also, George Sr. is frustrated when someone else gets credit for his football wins.

Ross struggles to maintain a long-distance relationship. Chandler tries to get a date for Rachel. Monica schemes to establish authority at her new restaurant job.

Phoebe's half-brother makes an astounding announcement and a thought-provoking request. Joey finds himself in a class struggle.

Phoebe finds out whether she is pregnant or not. A simple challenge escalates into a full-blown contest between the guys and the women.

Rachel schemes to get a handsome client to ask her on a date. Chandler's jealousy causes problems with his girlfriend.

Charlton Heston finds Joey in a compromising position during a movie shoot. Rachel regrets asking Ross for a favor.

Chandler's annoying former girlfriend reappears. Ross plays rugby to impress Emily with painful results.

Trying to become better acquainted with her sexy client, Rachel inadvertently thwarts Ross' plans for a romantic evening with his girlfriend.

Monica helps Ross tell his girlfriend that he loves her. Phoebe gets some surprising news about her pregnancy.

Ross and his ex-wife become jealous when their lovers go to England together. Rachel's plans to seduce her boyfriend go awry.

Drastic changes occur in Ross' relationship with Emily. Monica and Rachel will do anything to get their old apartment back from the guys.

Rachel reacts drastically to Ross' engagement. Chandler becomes exasperated by Joey's snoring.

Rachel and the engaged Ross reminisce separately about when they dated each other. The friends get invitations to Ross' wedding but not all of them are going.

Penny's flirtatious sales pitch leaves a doctor-client smitten and the guys must pitch in to help her deal with him, while Bernadette and Amy debate whether female scientists ought to play the sexuality card.

Amy and Bernadette organize a prom to be held atop the guys' apartment complex but Sheldon is leery of all the prom pomp, circumstance and romancing that goes with it.

Leonard needs surgery for a deviated septum, and Sheldon gets his nose out of joint because he feels an operation is too dangerous and that his roommate may not make it out alive.

It's a banner day for Sheldon as he bids a sad farewell to his Fun With Flags podcast. Meanwhile, Leonard, Howard and Raj probe a late professor's research in search of some hidden significance.

On Christmas Eve, Amy plans a traditional Victorian dinner, while Raj, Leonard and Howard scramble to remove a pigeon that flew into the clean room at the university.

While Raj eagerly awaits data from a space probe in which he was involved, Howard keeps distracting him. Later, dress shopping with Penny and Amy doesn't exactly prove to be a good fit for Leonard and Sheldon.

Sheldon becomes concerned that his cushy lifestyle is impacting his professional progress and keeping him from achieving scientific renown, so he asks the gang to make life more difficult for him.

An online troll rips Leonard and Sheldon's published physics paper, so the guys rally to defend the two and expose the bully, while a girls night out leads to Penny, Amy and Bernadette dishing about embarrassing past events.

Mary struggles to make new friends while Mandy pushes Georgie to date another woman.

Sheldon learns the university is building a database without him. Also, Mary takes care of a bedridden Mandy and Meemaw.

Mary butts heads with Mandy's mother, and Sheldon attempts male bonding.

Paige drags Sheldon to a college party, and Missy gets caught in a lie.

The Coopers can't be found as Mandy goes into labor. Also, Sheldon is excited about the launch of his database.

Sheldon confronts the failure of his database. Georgie and Mandy struggle as new parents. Missy feels forgotten.

Joey loses Ross' treasured wedding ring. Phoebe has extreme mood variations from her pregnancy.

Rachel stays home while the others go to England for Ross' wedding.

Rachel frantically tries to get to London before Ross marries Emily. Ross' father clashes with Emily's.

Will Emily forgive Ross before their honeymoon? Monica and Chandler agree to end their new relationship.

Ross' new wife won't speak to him. Rachel appoints Monica her advisor in romance. Phoebe feels neglected.

While Phoebe delivers triplets, Joey experiences his own pain. Monica plans a date with a male nurse to spite Chandler.

Joey challenges Phoebe to perform a completely selfless act. Monica gets upset when Chandler gloats about sex. Ross might finally reconcile with Emily but he must make a tough decision.

Ross tells Rachel that he cannot be around her once Emily comes to New York. Chandler and Monica try to have a romantic weekend.

Will Ross obey Emily and move away from his friends? Monica and Rachel meet a monster.

Joey and Chandler regret letting Ross move in with them. Rachel schemes to get her new neighbor to ask her on a date.

The friends find out about Monica's worst Thanksgiving ever.

Joey becomes exasperated from hiding Chandler and Monica's secret. Ross gets in trouble when he expresses his rage.

Amid the excitement of Stuart reopening his comic-book store, Howard gets some unsettling news; and after teaching Sheldon how to "let it go," Penny doesn't practice what she preaches when she learns something maddening about Amy.

An experiment designed to make participants fall in love piques Penny and Leonard's interest, so they decide to put it to the test. Meanwhile, Leonard, Amy, Raj and Emily have an encounter with a "zombie."

There's trouble in paradise when Amy discovers Sheldon signed up for a one-way mission to colonize Mars, and the two get into a dogfight at a pet store. Meanwhile, Leonard makes a very "adult" purchase for Penny.

An electrical short thaws the last meal that was cooked by Mrs. Wolowitz, and the gang ponders what to do with it, while Sheldon and Leonard's work is featured in a magazine, but only one receives credit.

A speaking engagement at UC Berkeley puts Leonard and Sheldon in a galaxy not too far, far away from their idol George Lucas' Skywalker Ranch, and they considrer dropping by.

When Sheldon and Amy build a fort, they come to a crossroad in their relationship. Wolowitz is shocked when a man claiming to be his half-brother shows up. When Penny is invited to be on Wil's podcast, she and Leonard have an argument.

In the event of alien contact, NASA asks Raj to craft a message for the extraterrestrials, and the guys battle over how it should be handled. Meanwhile, Penny must decide between auditioning for a film role or keeping her job in pharmaceutical sales.

Wolowitz questions his abilities when he and Sheldon can't get a drone to fly. A canceled flight nearly prevents Leonard from giving the commencement address. Raj pits his parents against each other when his father cuts him off financially.

Financial fraudster Will Ferrell hires Kevin Hart to 'coach' him on prison life as his sentence approaches in this comedy.

Following in his father's footsteps and hoping for some family bonding, Rusty Griswold surprises his wife and their two sons with an ill-fated cross-country trip back to America's favorite family fun park before it closes forever.

Missy steals her dad's truck and hits the road with her friend Paige.

Georgie goes on a birthday date, and Mary confronts Brenda about her relationship with George. Also, Sheldon takes an interest in Missy's favorite TV show.

Sheldon wants to search for life on other planets, and Mandy answers Georgie's marriage proposal. Also, Missy is caught between two friends.

Mandy gets an exciting job opportunity, and Sheldon worries that he's falling behind. Also, Georgie takes his daughter to work.

The gambling room gets broken into, and Sheldon wants to study abroad. Also, Missy makes a new friend.

Mandy surprises Georgie with a spa weekend, and Sheldon prepares for his summer in Germany.

A bored Ross creates havoc in Joey and Chandler's lives. Rachel is disturbed by her date's inappropriate relationship with his sister.

On New Year's Eve, the friends make resolutions for the coming year but keeping them proves difficult.

Chandler's behavior toward his boss annoys Monica. Ross' latest romance astounds everyone.

Phoebe meets another long-lost relative. Joey wears a shoulder bag.

Chandler and Monica's relationship becomes less of a secret. Ross must prove to his boss that he's sane in order to return to work.

Chandler thinks Monica wants more from their relationship. Ross fails to impress his new neighbors.

Joey wonders if he is in love with Monica. Phoebe impersonates a police officer.

Rachel interviews for a great job but she may get it for the wrong reason. Monica competes to have a better relationship than Phoebe's.

Rachel submits to peer pressure at work. Joey and Ross' son audition for the same commercial but only one can get the part.

Ross' flirting technique fails to impress a cute pizza-delivery woman. A surprise awaits Joey when he tells everyone about his big television appearance.

The guys enjoy riding along with a police officer until a gunshot is heard. Rachel overhears a telephone message for Ross from his second ex-wife.

Phoebe's boyfriend wants her to move in with him. Ross and Joey involve Chandler and Monica in an obsessive game.

Leonard and Sheldon's mothers come to town to celebrate their sons getting an award, but the opinionated women engage in an altercation over religion.

In the Season 8 finale, Leonard and Penny are pressured to set a wedding date by Sheldon, whose relationship with Amy has taken an interesting turn.

Season 9 premiere, Penny has a problem dealing with Leonard's confession about having kissed another woman, while Sheldon is confused about Amy calling a timeout on their relationship.

To ease Penny's mind, Leonard pays a visit to the woman he kissed during his expedition to the North Sea, while Sheldon's breakup with Amy leads him to retaliate by shooting a special episode of "Fun with Flags".

The guys surprise Leonard with a belated bachelor-party weekend in Mexico, but their plans hit a bump in the road when they get a flat tire on the way. Meanwhile, the girls lean on Penny to tell her family that she and Leonard eloped.

Sheldon reverts back to 2003 when he learns that Leonard and Penny are moving in together. Meanwhile Howard and Raj form a band to play at the comic book store.

When Barry Kripke gives the guys fencing lessons, he makes a point of letting Sheldon know he's interested in dating Amy. Stuart has trouble getting female customers at the Comic Book Store, so Penny, Amy and Bernadette stop by to help out.

A helium shortage leads Sheldon and Leonard to do business with a dealer in the black market in order to acquire some of the element for an experiment they need to complete.

Peter Quill and his fellow Guardians are hired by a powerful alien race, the Sovereign, to protect their precious batteries from invaders. When it is discovered that Rocket has stolen the items they were sent to guard, the Sovereign dispatch their armada.

Captain Marvel gets caught in the middle of an intergalactic war between two extraterrestrial races.

Criminal mastermind Debbie Ocean and seven other female thieves try to pull off the heist of the century at New York's annual Met Gala. Their target -- a necklace that's worth more than $150 million.

Joey's first major film role leads to an unexpected experience in Las Vegas. Phoebe can't remember why she hates Ross.

The gang travels to Las Vegas, Nevada, where more than one surprise awaits. After Ross misinterprets Rachel's actions, a war of public humiliation results.

Monica and Chandler get lucky in Las Vegas, Nevada. Rachel makes Ross regret playing a prank on her. Joey schemes for fame and fortune.

Two of the friends leave Las Vegas married. Joey and Phoebe have a cross-country adventure.

Monica is bewildered by Rachel's reaction to a change in their living arrangement. Phoebe tries to make Ross confront his feelings for Rachel.

Criminal mastermind Debbie Ocean and seven other female thieves try to pull off the heist of the century at New York's annual Met Gala. Their target -- a necklace that's worth more than $150 million.

Captain Marvel gets caught in the middle of an intergalactic war between two extraterrestrial races.

Now just friends, Sheldon and Amy spend Thanksgiving at the aquarium, a reluctant Wolowitz volunteers at a soup kitchen with Bernadette, Raj and Emily, and Penny realizes that Leonard knows a bit more about her than he's let on.

God only knows what song is constantly playing in Sheldon's head, but it reminds him of Amy and leads to a surprising revelation. Meanwhile, she is back in the dating game.

Professor Proton visits Sheldon in a dream and gives him Obi-Wan Kenobi-like advice about whether to go see the new "Star Wars" film or spend the time with newly reunited girlfriend Amy on her birthday.

Penny entices Leonard to meet with a psychiatrist and the results are surprising, Stuart moves out of the Wolowitz house, and Howard and Bernadette find themselves at a loss.

Dealing with an under-the-weather Sheldon is so draining for Penny, Leonard, and the gang, that they decide to treat themselves to a Sheldon-less weekend.

Sheldon's grandmother, aka Meemaw, visits and there's friction between her and Amy, which intensifies after the elderly woman blurts out a secret about Sheldon.

Sheldon and Amy celebrate Valentine's Day with an episode of Fun With Flags, Leonard and Penny feel the pangs of aging, and Howard and Bernadette are surprised by what they find in their hot tub.

The gang learns Bernadette is pregnant and celebrates by singing karaoke. Meanwhile, Wolowitz freaks out over the pregnancy announcement and becomes convinced he must make more money to provide for the baby.

Following in his father's footsteps and hoping for some family bonding, Rusty Griswold surprises his wife and their two sons with an ill-fated cross-country trip back to America's favorite family fun park before it closes forever.

A 70-year-old widower has discovered that retirement isn't all it's cracked up to be. Seizing an opportunity to get back in the game, he becomes a senior intern at an online fashion site, founded and run by a woman of high power.

While Phoebe delivers triplets, Joey experiences his own pain. Monica plans a date with a male nurse to spite Chandler.

The friends cause havoc in the maternity ward as Rachel begins childbirth.

The friends cause havoc in the maternity ward as Rachel begins childbirth.

The six friends say goodbye and embark on the next chapters of their lives.

The six friends say goodbye and embark on the next chapters of their lives.

Every year in the ruins of what was once North America, the nation of Panem forces each of its twelve districts to send a teenage boy and girl to compete in the Hunger Games.

Sheldon and Mary head to Germany while the rest of the Cooper family braves a tornado that is heading straight for Medford.

Despite Phoebe's admonitions, Ross makes a drastic decision about Rachel. Chandler and Monica bicker over their living arrangements.

Injured Joey must get an acting part in order to qualify for health insurance. Rachel finally learns the truth about her marriage to Ross.

Rachel forces Ross to terminate their marriage. Phoebe's first triplet baby-sitting experience proves stressful. Joey pretends to own a sports car.

The guys and the women prepare for big changes in their living arrangements.

Chandler learns how obsessively neat Monica is when he attempts to do her a favor. Joey desperately tries not to flirt with his sexy new roommate.

The guys explore their femininity. Phoebe causes trouble when she kisses someone at Rachel's work.

On Thanksgiving, Chandler tries to gain favor with Monica's parents but an old secret involving Ross causes problems. Undomestic Rachel's dessert proves intriguing.

Joey plots the perfect opportunity to kiss Janine. Ross and Monica resurrect their dorky high school dance routine for a television special.

Joey finally dates Janine but she doesn't like his friends. Rachel worries Phoebe won't appreciate the way she furnishes their apartment.

Ross and Chandler bicker over which of them created a raunchy joke. Phoebe antagonizes Monica and Rachel with her candor. Joey reluctantly takes a waiter job at Central Perk.

Rachel tries to help her pampered younger sister, Jill, find independence but Jill flirting with Ross is not part of the plan. Monica won't admit that she is sick.

Rachel's sister Jill wants Ross but not for the reasons he thinks. Chandler astounds the others with his inability to express emotions. Is Phoebe starring in pornography?

Sheldon and the gang celebrate his birthday and he's surprised by a special guest.

Howard reconsiders entering into a legal partnership with Leonard and Sheldon regarding the patent for the infinite persistence gyroscope. Also, the women offer Raj dating advice after Emily reaches out to him following their breakup.

Sheldon shocks Amy with a startling revelation after she buys him a new laptop. Meanwhile, Raj throws Leonard and Howard under the bus after they lie to their wives and sneak off to an early screening of a movie.

Sheldon shares a secret about Leonard when the two go on a weekend trip with Penny and Amy; Raj goes all out with pregnancy gifts.

During a group get-together, a minor argument between Sheldon and Leonard turns into a heated debate, leaving the rest of the gang to choose sides.

Sheldon stays behind to spend quality time with the pregnant Bernadette when the rest of the gang toddles off to a wine-tasting event where they run into Penny's former boyfriend, and Raj introduces his new girlfriend.

When Sheldon decides he'd rather go to a movie screening than hang out with Amy, he hires Stuart to spend the day with her. Meanwhile Leonard's mother visits, and Penny just can't seem to connect with her.

In the Season 9 finale, Leonard's recently divorced parents roll into town, as does Sheldon's holy-roller mother, and all hell breaks loose.

In the Season 10 premiere, the gang deals with the awkward aftermath of an overnight liaison between Sheldon's mother and Leonard's father. Meanwhile, Penny's dysfunctional family is in town for the wedding.

The guys heads are in a spin when an Air Force bigwig approaches them about their revolutionary gyroscope invention, and Bernadette is upset with Penny after she accidentally leaks a secret to the mom-to-be's coworkers about her being pregnant.

Howard and Leonard are putting in late nights at work and Sheldon is having trouble keeping up, Raj and a pregnant Bernadette spend a day together, and Penny and Amy take in a faculty party.

Sheldon and Amy decide to move in together when her apartment floods. Meanwhile, Howard and Bernadette become upset when Raj learns the gender of their baby before they do.

Amy and Sheldon's live-in relationship may be in the toilet after he accuses her of not following the bathroom schedule. Meanwhile, Howard and Bernadette's secret staycation is interrupted by interfering interlopers who are sneaking into their hot tub.

Feeling his fetal offspring kick sends Howard on a baby-items buying binge with Raj, Sheldon and Amy host a brunch in their new digs, and Penny, by virtue of her virtuoso performance in "Serial Apist," is invited to a sci-fi convention.

Hayley makes Jeff get a friend to add some mystery to their relationship but gets more mystery than she bargained for. Francine attempts to grow the world's longest fingernails.

The Smiths get new neighbors! Meanwhile, Roger dreads having to be a little boy's kite for a day.

Francine becomes an overnight sensation when a famous art dealer discovers her homemade pottery.

Hayley searches for a runaway Steve so they can go to a Shaggy concert.

Klaus house sits for the Smiths while they are away on vacation. Meanwhile, Roger investigates the origin of powerful winds plaguing the Eastern Seaboard.

Social Services threatens to take Steve away from the family when someone files a complaint about Steve's chaotic home life.

Stan and Roger go on a mission to leave their mark on humanity. Then, Jeff finally deals with the reality of losing his signature hat.

In order to have a chance with a girl, Steve and Snot must track down a keg of 4Loko.

Francine enters the strange and dangerous world of poker in order to learn how to hide her true feelings from Steve and Hayley.

Suspicious about Hayley's mysterious, newfound wealth, Francine decides to get to the bottom of it. Roger sets out to make Stan an internet celebrity.

The friends fantasize Rachel and Ross are in respective loveless marriages. Monica is an overweight virgin. Poor Chandler works for television star Joey, and Phoebe is an overstressed stockbroker.

In the speculative fantasy, Ross initiates romantic advances with his wife Carol. Chandler and Monica help each other overcome loneliness, Rachel learns the truth about her husband and Phoebe sneaks out of the hospital.

Chandler gets into trouble with his homemade gift for Monica. Ross tries to teach martial arts to Rachel and Phoebe. Joey hires a look-alike.

When a fire damages their apartment, Rachel and Phoebe must choose between living temporarily with Joey or Monica. Ross gets into trouble where he teaches.

Ross worries when his student/girlfriend goes on vacation with her wild friends. Meanwhile, Joey's refrigerator breaks down.

Primarily composed of clips from earlier shows, Joey auditions for a major television role but Chandler almost ruins everything.

Ross is nervous about meeting Paul, Elizabeth's dad, and invites the gang to the coffeehouse for moral support.

Elizabeth and Ross decide to hide their relationship from her father and head up to his cabin for the weekend.

Phoebe helps Chandler pick out an engagement ring for Monica.

Chandler plans to propose to Monica.

Monica asks Chandler to be her husband.

Monica excitedly reveals her good news to everyone but Rachel and Ross upstage her. Chandler has trouble making love.

Amy and Sheldon's live-in relationship may be in the toilet after he accuses her of not following the bathroom schedule. Meanwhile, Howard and Bernadette's secret staycation is interrupted by interfering interlopers who are sneaking into their hot tub.

Feeling his fetal offspring kick sends Howard on a baby-items buying binge with Raj, Sheldon and Amy host a brunch in their new digs, and Penny, by virtue of her virtuoso performance in "Serial Apist," is invited to a sci-fi convention.

In order to remain Sheldon's roomie, Amy fibs about repairs being made to her apartment. Later, they present a episode of "Fun with Flags" in Penny's apartment.

A successful gene experiment leaves Sheldon excited to procreate with Amy, and he pulls out all stops to get her on board. Meanwhile, Raj is reluctant to reveal what the new woman in his life does for a living.

Meet 9-year-old Sheldon and his family on the series premiere! Sheldon learns that his high intelligence isn't always helpful growing up in East Texas, where church and football are king.

Sheldon goes on a quest to make his first friend.

Sheldon's faith is shaken when his dad goes to the hospital.

Monica is outraged to find out what her parents did with her wedding fund. Joey discovers Rachel's late-night reading material.

Monica desperately tries to figure out a secret cookie recipe. Chandler fails to impress Monica's father.

Rachel is in a quandary when a sexy but unqualified man applies to be her assistant. Chandler, Monica and Ross tell embarrassing secrets about one another.

Joey tries to teach Chandler how to smile for the camera. Phoebe and Ross bicker over their divorcing friends.

Rachel and Phoebe compete to be Monica's maid of honor but Monica doesn't want to make the decision. Chandler tries to apologize to a girlfriend from his youth.

Chandler's former girlfriend manipulates Chandler and Monica. Rachel and Phoebe meddle in Joey's relationship.

Chandler's irrational fear causes problems when Phoebe brings home a cute dog. Rachel's assistant gives her a Thanksgiving surprise.

Rachel gets in trouble for dating her assistant. Monica tries to become friendlier with her neighbors. Phoebe needs lessons in riding a bike.

Ross teaches Ben about Chanukah. Phoebe worries that Rachel prefers living with Joey.

Phoebe's former boyfriend returns for one night only but Joey could ruin their plans. Monica plots revenge on her cousin's wedding day.

Monica falls asleep during sex. Rachel argues with Tag. Ross and Joey get stranded on the roof.

Phoebe becomes involved with a suicidal office worker. Rachel breaks Joey's favorite chair. Monica's beloved childhood belongings are destroyed.

A geologist coworker's MacArthur Genius fellowship award leaves Sheldon stone cold jealous. Meanwhile, Howard stumbles upon a remote-control Stephen Hawking action figure that he invented. Hawking appears as himself.

A great divide develops between Sheldon and Leonard when it comes time to divvy up their shared belongings. Meanwhile, with Bernadette heading into her pregnancy homestretch, Raj and Stuart battle to be the one providing her the most help.

The Wolowitz baby arrives, while Sheldon and Amy celebrate Amy's birthday.

Sheldon and Amy visit Leonard and Penny for the first time since the holidays and share details about their terrible trip to Texas.

After a marital disagreement, Penny takes off for a spa weekend with Amy, and Sheldon steps in to play peacemaker for the squabbling newlyweds. Meanwhile, Howard and Raj do battle with a noisy floor in the baby's room.

Sheldon decides to test an MIT invention that can help read people's emotions. Meanwhile, Leonard has trouble hiding his emotions when Penny announces her brother is going to visit, and Raj gathers former girlfriends to ask for their dating advice.

With Sheldon hindering progress on the guidance-system project, Leonard and Howard figure the only way they can get back on track is to engineer a distraction by getting him tickets to a historic railroad.

Amy is incensed when she discovers Sheldon has shared intimate relationship information with people at the University, and Raj is knocked for a loop when his father stops sending financial support.

Sheldon refuses to eat solid food after a choking scare.

Sheldon helps his father coach the football team.

Sheldon is determined to prove a NASA rep wrong.

George takes his sons to see a space shuttle launch.

Sheldon tutors his brother when his grades threaten football.

Sheldon interviews with a school for gifted children.

Rachel's 30th birthday prompts the friends to reminisce about their own 30th birthdays.

Joey's character on a daytime drama becomes more prominent to the chagrin of the show's diva star. Phoebe and Rachel argue over who should return a sexy man's misplaced cell phone to him.

Chandler finds out who Monica really wanted to have sex with on the night they became lovers. Ross is furious after Rachel teaches Ben practical jokes.

Monica battles another shopper for the perfect wedding dress. Ross and Joey compete for the same woman.

Joey overreacts at a daytime drama awards show.

Monica's gorgeous cousin unwittingly wreaks havoc on Chandler and Ross. Rachel and Phoebe hastily plan a surprise bridal party for Monica.

Rachel reveals a titillating secret about her and a former sorority sister. Ross and Chandler compete for wedding tuxedos.

As Monica and Chandler prepare their wedding vows, they and their friends reminisce.

Chandler confronts his estranged cross-dressing father. Rachel gets into trouble driving Monica's Porsche.

On the eve of the wedding, Ross searches for missing Chandler, who has doubts, while the girls distract unsuspecting Monica.

Monica remains blissfully unaware of the potential disasters on her wedding day.

The reception following Monica and Chandler's wedding is almost upstaged by the news that a member of the group might be pregnant.

Without financial backing from his father, Raj finds himself in a cash crunch and turns to Sheldon to help him get his head above water. Meanwhile, Penny considers crashing the guys' annual Comic-Con getaway.

Leonard and Penny offer Sheldon's old room to Raj after he moves out of his apartment.

Raj moves in with Leonard and Penny and a period of adjustment begins for the three, while usually self-centered Sheldon shows surprising interest in Amy's work.

Sheldon is working overtime and pushing himself when he collaborates on projects with Leonard and Howard, and another one with Amy, all on the same day. Bernadette's maternity leave is running out and she must face going back to work.

Leaving baby Halley in day care proves to be tough for Bernadette after she starts back to work, and geologist Bert digs up a girlfriend, but some of his colleagues think she's a gold digger.

Penny's job offer from a former boyfriend doesn't sit well with Leonard.

Leonard, Sheldon and Wolowitz celebrate the successful completion of their top-secret military project, until an unpleasant surprise leaves their heads spinning. Amy considers an offer of a summer position as a visiting researcher.

On the Season 10 finale, Sheldon's former admirer, Dr. Ramona Nowitzki, turns up while Amy is visiting Princeton, and the gang is extremely concerned.

Season 11 begins with Amy giving Sheldon an answer to his marriage proposal. Meanwhile, Howard and Bernadette struggle with some unexpected news.

Leonard angers the university and the entire physics community when he gives an embarrassing radio interview. Meanwhile, Amy and Bernadette bond over having to hide their success from Sheldon and Howard.

Amy records Sheldon talking in his sleep and tries to convince him that he has a more laid-back side. Meanwhile, Raj and Stuart compete to win the heart of Bernadette's new co-worker.

Wolowitz and Sheldon bond over their relationships with their disappointing fathers when they drive to the desert to shoot off a model rocket. Leonard's mom finds a new best friend in Penny, much to Leonard's dismay.

Sheldon and Raj confide in Bernadette when they can't handle Amy and Howard working together. Penny and Leonard learn new tactics on how to deal with Sheldon and they come from an unlikely source.

Sheldon goes head-to-head with Wil Wheaton for the role of the new Professor Proton. Penny steps in and takes care of Halley when Bernadette and Howard both wind up on bed rest.

As the Avengers and their allies continue to protect the world from threats too large for any one hero, a new danger emerges: Thanos, who threatens the fate of Earth and life itself.