Howard invites Sheldon to travel to Houston with him in an attempt to improve their friendship, while Penny's offered an embarrassing role and Raj asks Amy for help with a girl.
Leonard's purchase of a dining room table for the apartment nearly causes Sheldon to break up with Amy, while Howard is offered a chance to return to space again.
Love is in the air when Amy convinces Sheldon to join her (as well as Howard and Bernadette) for a romantic weekend in Napa Valley to celebrate Valentine's Day.
After they miss out on Comic-Con tickets, the guys mock Sheldon for trying to hold his own comic book convention...until he winds up spending a wild night with JAMES EARL JONES.
After Penny quits her job and Sheldon is forced to take another vacation, the two spend a lot of time together.
When Penny's big acting break on NCIS is a bust, Leonard struggles to help her, which results in Penny asking Leonard a bold relationship question.
While Sheldon is away in Texas, everyone gathers to decorate the apartment Christmas tree, and they each realize how much he has changed their lives.
Sheldon faces a crisis after Leonard disproves his accidental scientific discovery. Meanwhile, Raj must stay with Howard & Bernadette for a week.
An upset Sheldon protests when the entire gang drags him to Mrs. Wolowitz's house for Thanksgiving. Meanwhile, Penny and Leonard must deal with a mistake from her past.
Sheldon punishes Leonard for a past mistake by making him "walk a mile in his shoes." Meanwhile, Penny confronts Raj's ex-girlfriend, Lucy (guest star KATE MICUCCI).
Sheldon feels slighted when Professor Proton (BOB NEWHART) seeks advice from Leonard instead of him, and he seeks revenge by befriending a rival science TV host, BILL NYE.
Sheldon's latest scientific breakthrough makes him feel like a fraud - and threatens to haunt him forever. Meanwhile, Howard's romantic gesture to Bernadette causes Penny to step up her game with Leonard.
Sheldon must decide how much "Amy time" is too much after she takes a job at his university, and their relationship is put to the test. Meanwhile, Howard finds himself sleeping on Raj's couch after a fight with Bernadette.
After Amy ruins one of Sheldon's favorite movies - Raiders of the Lost Ark - he gets defensive, seeking revenge. Meanwhile, Leonard discovers a way to get Penny to do anything; and Raj and Stuart create online dating profiles.
When the entire gang competes in a cutthroat scavenger hunt designed by Raj that tests their science knowledge and street smarts, it brings out the best - and worst - in everyone.
On the second part of the one-hour seventh season premiere, Raj gets consoled about his ex-girlfriend and Howard's relationship with his mother causes an unusual threat to his masculinity. KEVIN SUSSMAN returns as Stuart, the comic book store owner.
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