Looking for privacy, Johnny and Moira take the Mayor up on his offer of using his cabin for a night, while Alexis and David use the opportunity to throw a party.

Courteney must cut one of her Buttons from making mat at Daytona. Each of the team shares why Daytona is so important, but Courteney operates with her head over her heart and, after grueling tryouts, renders a heartbreaking decision.

At an annual cross-church party, Aaron waits to be baptised. But his head is turned by one congregation carrying rainbow flags. Fiona and Rachel argue over university.

Alan offends Charlie by choosing their crazy cousins as Jake's guardians. Later, as Charlie and Jake play basketball, Jake falls, hitting his head. Charlie rushes him to the emergency room and finds that his charm with women doesn't work with the admitting nurse.

Charlie agrees to meet with a former girlfriend who ended their relationship years earlier, leaving Charlie devastated. But Charlie's in for a huge surprise when he discovers that she is now a he, and he, Bill, wants to be Charlie's friend.

After Alan and Charlie have a fight about Alan's role in the house, Alan packs Jake up and moves in with his mother. Evelyn and Teddy don't want Alan there and go to great lengths to reconcile the siblings.

Charlie writes children's songs and finds success as Charlie Waffles. The kids and their parents love him, even signing CD-s of his jingles. However, Charlie's new found fame irritates Alan.

Charlie & Alan are introduced to Teddy's daughter Courtney. Teddy warns Charlie to stay away from her but Charlie, unaware of what she is capable of, sleeps with her and then gets blackmailed into buying a new Ferrari.

Frankie and Mike tell Brick the true story of how he was born.

Brick wants his independence from being Frankie's errand boy.

Mike's brother visits for Thanksgiving.

The truth comes out on the paintball field.

Penny's ex-boyfriend asks Leonard for a huge favour.

A rival team of physicists tries to take credit for Super Asymmetry.

Phoebe's half-brother visits, but they have trouble bonding. Joey attempts to build an entertainment centre whilst Ross is challenged to name the five celebrities he'd like to sleep with the most.

When Janice asks the gang if any of them have ever slept together, the friends flash back to a time three years before, where some dark secrets are revealed.

Joey sees Janice and her soon-to-be-ex-husband, "The Mattress King", kissing. Rachel attempts to have her father and Ross bond but things don't go as planned and Joey gets a job teaching a soap opera acting class.

Joey tells Chandler he saw Janice kissing her ex-husband. Monica accidentally bumps Ben's head against a post and Phoebe is convinced she's cursed because every time she goes to the dentist someone around her dies.

After Alan and Charlie have a fight about Alan's role in the house, Alan packs Jake up and moves in with his mother. Evelyn and Teddy don't want Alan there and go to great lengths to reconcile the siblings.

Charlie writes children's songs and finds success as Charlie Waffles. The kids and their parents love him, even signing CD-s of his jingles. However, Charlie's new found fame irritates Alan.

Charlie & Alan are introduced to Teddy's daughter Courtney. Teddy warns Charlie to stay away from her but Charlie, unaware of what she is capable of, sleeps with her and then gets blackmailed into buying a new Ferrari.

Frankie and Mike tell Brick the true story of how he was born.

Brick wants his independence from being Frankie's errand boy.

Mike's brother visits for Thanksgiving.

The truth comes out on the paintball field.

Penny's ex-boyfriend asks Leonard for a huge favour.

A rival team of physicists tries to take credit for Super Asymmetry.

Phoebe's half-brother visits, but they have trouble bonding. Joey attempts to build an entertainment centre whilst Ross is challenged to name the five celebrities he'd like to sleep with the most.

When Janice asks the gang if any of them have ever slept together, the friends flash back to a time three years before, where some dark secrets are revealed.

Joey sees Janice and her soon-to-be-ex-husband, "The Mattress King", kissing. Rachel attempts to have her father and Ross bond but things don't go as planned and Joey gets a job teaching a soap opera acting class.

Joey tells Chandler he saw Janice kissing her ex-husband. Monica accidentally bumps Ben's head against a post and Phoebe is convinced she's cursed because every time she goes to the dentist someone around her dies.

Alan learns Charlie stole away a girl he liked in high school. Seeking revenge he steals Charlie's French girlfriend Gabrielle. However, things don't really work out like he planned due to Gabrielle's behaviour in bed.

Alan is unhappy about his sex-life with his new girlfriend Donna and breaks up with her. Charlie helps a now-free Jake hit on a girl while the two are out dining but it ends up with Charlie getting pepper sprayed.

Charlie sleeps with a woman who is sick & catches her flu. With nobody in his family there to look after him, Rose (back from England) offers her help. Alan feels Jake is pulling away from him which makes him feel sad.

Charlie sleeps with a woman who is sick & catches her flu. With nobody in his family there to look after him, Rose (back from England) offers her help. Alan feels Jake is pulling away from him which makes him feel sad.

Frankie's parents visit for the 12 Days of Christmas.

Frankie and Mike decide to regain control of their lives.

Mike's livid that Frankie mistakenly paid $200 for eye cream.

Sheldon must choose between his friends or following the rules.

Penny tries to divert Leonard's plans to be a sperm donor.

The guys try to crash Wil Wheaton's celebrity D&D game.

Emotions become the feast of the day when the gang plays a game of touch football. Joey & Chandler argue over who gets to date a beautiful Dutch woman and Ross & Monica argue over winning in a case of sibling rivalry.

Rachel makes a rash decision after Gunther tells her she needs retraining. Phoebe tries to help Joey when he gets a job selling Christmas trees and Ross accidentally breaks a girl's leg and tries to make it up to her.

Ross is suspicious about Rachel's possible job offer from a good-looking stranger. A drunken Chandler fools around with one of Joey's sisters but can't remember which one.

Ross becomes jealous when he thinks he catches Rachel's new co-worker whispering sweet nothings in her ear. Joey is forced to teach a very hard dance to an entire Broadway cast after lying on his resume.

Ted starts a risky affair with a married woman and becomes emotionally invested; Matty and Susan try to figure out the cause of Matty's erectile dysfunction.

Judith's sinister-but-sexy sister, Liz, plans to attend Jake's 11th birthday party. Alan asks Charlie to behave. But when Liz arrives, she ignores Charlie and flirts with Alan instead. Liz proceeds to cause a commotion between her sister and her ex-brother-in-law.

Jake becomes a brooding musician when he continuously plays "Smoke on the Water" on his guitar with an ever-present grumpy attitude. Finally, Judith convinces Alan that Jake needs professional assistance, and they enlist the help of Dr. Linda Freeman.

Ned tags along on Mare’s consumer sting story after Esmeralda tells him a bunch of things that get in his head; Oscar has to stick his neck out in a budget meeting; Detrick and Nicole play two truths and a lie until it blows up.

Kirsty and Ian explore new sides of their sexuality. The boys’ hunt continues.

With Leonard away, Sheldon and Penny spend quality time together sharing intimate secrets. Also, Wolowitz helps Raj get over his ex-girlfriend.

Leonard and Sheldon's friendship is tested; Wolowitz's relationship with his mom causes a threat to his masculinity.

When the entire gang competes in a scavenger hunt designed by Raj, it brings out the best - and worst - in everyone.

Beverly Hofstadter writes a psychology book about Leonard which Penny buys and reads. Sheldon wants to ruin something for Amy after she ruins an Indiana Jones movie for him and Raj and Stuart try online dating.

Amy starts working at Caltech which causes friction with Sheldon. Howard agrees with Sheldon who mentions this to Bernadette causing a big fight for the Wolowitzes.

Sheldon's latest scientific breakthrough leaves him feeling like a fraud and a romantic gesture between Howard and Bernadette causes Penny to up her game with Leonard.

When Professor Proton asks Leonard for help with an experiment, Sheldon retaliates by befriending Proton's rival, Bill Nye.

When a mistake comes to light, Sheldon makes Leonard walk a mile in his shoes; Penny decides to confront Raj's ex.