
The Big Bang Theory
Worlds collide in Season 3! A love affair with Penny has opened a big, wide, wonderful world of romance for Leonard. But Sheldon likes the world just the way it was, thank you. All of which makes for a zany comic triangle with brainy, clueless Sheldon and practical, grounded Penny hilariously vying for the role of hypotenuse.
When Sheldon learns the guys tampered with his expedition data he got from the arctic, he leaves to Texas in disgrace. This results in the guys following him, which threatens Leonard's hope for some romantic time with Penny and the guys' friendship with Sheldon.
Guest Stars:
Leonard and Penny struggle to recover from an awkward first hookup while Sheldon and Howard stake their best comic books on a bet to determine the species of a cricket.
Guest Stars:
Lewis Black
Howard and Raj visit a Goth nightclub to pick up women while Sheldon attempts to build a better Penny using chocolate-based behavior modification.
Guest Stars:
Molly Morgan, Sarah Buehler, Andy Mackenzie
Raj must find a new job or be sent back to India, but Sheldon has a solution, which leaves Leonard and Penny dealing with Howard as a third wheel.
Guest Stars:
Elizabeth Bogush, Oliver Muirhead
After overhearing that Wil Wheaton is entering a trading-card competition, Sheldon decides to enter it himself. Meanwhile, Penny sets up one of her friends on a date with Wolowitz.
Guest Stars:
Melissa Rauch, Kevin Sussman, Wil Wheaton
Sheldon becomes Leonard's teacher in order to understand football, while an incident with flying a kite threatens Howard and Raj's friendship.
Guest Stars:
Zachary Abel, Jason Mesches
A squabble between Leonard and Penny sees Sheldon playing mediator, though out of his own incovenience from the sitiation rather than altruism.
Guest Stars:
Kevin Sussman, Alice Amter, Brian George, Carol Ann Susi
With Leonard, Howard and Raj away camping in the desert, an injured Penny has only Sheldon to rely on.
After he's humiliated on National Public Radio, Sheldon vows to destroy Kripke, while Wolowitz tries not to destroy his new relationship with Bernadette.
Guest Stars:
Melissa Rauch, John Ross Bowie, Carol Ann Susi, Ira Flatow, Katee Sackhoff
Penny gets help from Sheldon in order to understand what Leonard's work is, while Wolowitz develops a jealousy when Leonard starts hanging out with his new girlfriend.
Guest Stars:
Melissa Rauch, Carol Ann Susi
A Christmas visit from his mother has Leonard discovering she's kept a lot of news from him that she shares with Sheldon and worrying if she'll approve of his romance with Penny.
Guest Stars:
Christine Baranski
Leonard is aghast to find out a secret of Penny's: she believes in psychics. Meanwhile, Sheldon tries to assist Koothrappali in picking up a girl at a university mixer.
Guest Stars:
Melissa Rauch, Danica McKellar, David Trice, Jen Drohan
When their apartment is robbed, Leonard and Sheldon turn to their friends to create a state-of-the-art security system.
Guest Stars:
Julio Oscar Mechoso, Artie O'Daly
Sheldon's search for the answer to a physics problem leads him to work at the Cheesecake Factory with Penny.
Guest Stars:
Melissa Rauch, Yeardley Smith, Kevin Brief
Leonard can only bring one guest on a trip to see CERN's Large Hadron Collider (the world's largest and highest energy particle accelerator) in Switzerland on Valentine's Day.
Sheldon winds up in traffic court when he gets a ticket because of Penny.
Guest Stars:
Kevin Sussman, Marcus Folmar, Stan Lee, Steve Paymer
When the guys find a ring from "The Lord of the Rings" at a garage sale, it threatens to tear them apart.
Guest Stars:
Frank Maharajh
Sheldon's friends come to his aid when his fear of public speaking stands between him and a coveted award.
A fight between Leonard and Penny threatens their relationship, while Sheldon battles Wil Wheaton in bowling.
Guest Stars:
Kevin Sussman, Wil Wheaton
When Leonard and Penny aren't speaking, Sheldon goes to extremes to keep them both happy.
Leonard and Sheldon compete for the attention of a famous female physicist.
Guest Stars:
Judy Greer
Leonard tells Penny about how he met Sheldon for the first time...and what happened to the elevator.
Guest Stars:
Carol Ann Susi, Ed Lieberman, Ally Maki, Steven Yeun, Ajgie Kirkland
Laurie Metcalf, John Ross Bowie
24 Episodes