The Big Bang Theory

On the one-hour seventh season premiere, Sheldon and Penny bond in Leonard's absence, but it's Sheldon's feelings that are crushed when Leonard returns from the North Sea. Guest star REGINA KING returns as Mrs. Davis, the University's Director of Employee Relations.

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.

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.

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.

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.

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 feels slighted when Professor Proton (recurring guest star BOB NEWHART) seeks advice from Leonard instead of him, and he seeks revenge by befriending a rival science TV host, BILL NYE (guest starring as Himself). Meanwhile, Raj gets jealous when Howard crashes "girls' night."

Leonard tries to keep Sheldon from overreacting when a past mistake comes to light, but Sheldon punishes Leonard by making him "walk a mile in his shoes." Meanwhile, Penny confronts Raj's ex-girlfriend, Lucy (guest star KATE MICUCCI).

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.

Leonard and Amy help Sheldon cope with the shame he's feeling after his accidental contribution to science is disproved. Meanwhile, Raj must stay with Howard and Bernadette for a week. IRA FLATOW guest stars as Himself.

While Sheldon is away in Texas, everyone gathers to decorate the apartment Christmas tree, and imagines what their lives would be like if they had never met Sheldon.

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. Meanwhile, Sheldon tries to learn how to be funny and Raj tries to work on his "game" before talking to girls.

When Sheldon is forced to take a vacation, he tries to relax, but instead spends a lot of time with Penny after she quits her job. Meanwhile, Leonard struggles to be supportive of Penny and Bernadette seeks Stuart's help in replacing one of Howard's comic books.

After they guys can't get Comic-Con tickets, Sheldon decides to hold his own convention, and winds up spending a wild night with JAMES EARL JONES (guest starring as himself). Meanwhile, the girls see if they can act like "grown-ups." Star Wars icon CARRIE FISHER makes a cameo appearance as well.

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. Meanwhile, Leonard and Penny must rush Raj's dog to the vet.

When Leonard buys a dining room table, it causes Sheldon to reevaluate the changes in his life. Meanwhile, Wolowitz is offered a chance to go back to space and Bernadette struggles with whether or not to encourage him.

After the insults fly, Bernadette tries to broker the peace between Howard and Sheldon by having the two travel together to Houston in an attempt to improve their friendship. Meanwhile, Penny is offered an embarrassing movie role and Raj asks Amy to write to a woman on his behalf.

When Sheldon visits his mom (recurring guest star LAURIE METCALF) in Houston, he is forced to confront a new reality. Meanwhile, Raj's "Murder Mystery" party starts some fights within the gang.

While Raj is wracked with guilt over dating two women at the same time and Penny is wrestling with whether to take a role in a cheesy movie, Amy must help Sheldon through the even greater hell of choosing between two gaming systems.

Sheldon faces a personal crisis after deciding he's wasting his time with String Theory. Meanwhile, a double date between Raj, Emily and the Wolowitzes ends in embarrassment for Howard.

Leonard tries to help Sheldon free his mind by reinstating "Anything Can Happen Thursday," but when Sheldon tries to be spontaneous, it leads to unexpected friction between Penny, Amy and Bernadette. Meanwhile, Raj seeks Howard's help in preparing for a date with Emily.

May the "Fourth" Be With You! Professor Proton helps Sheldon cope with grief, while Leonard turns a relationship milestone into a competition with Penny. Meanwhile Amy and Bernadette make a "Star Wars Day gift for the guys.

A horrible day at work prompts Penny to evaluate her life choices - including taking a big step with Leonard. Meanwhile, Howard and Bernadette struggle to care for Mrs. Wolowitz, and Raj gets relationship advice from Sheldon.

With his entire world changing around him, Sheldon is forced to confront an uncertain future and considers a major move in the seventh season finale. Meanwhile, Raj and Emily take it to the next level, and Mrs. Wolowitz's injury is a major headache for Howard and Bernadette. Recurring guest star CHRISTINE BARANSKI returns as Leonard's mother, Beverly Hofstadter.