The Big Bang Theory
About the Show
Arch-nerds Leonard and Sheldon may know more than their fair share about subatomic particles, but when it comes to people in general, and women in particular, they're absolutely clueless...
Series 2 Summary
It's been a year, and the null hypothesis - Leonard failing to get together with Penny - seems to have prevailed. But there's still hope. And if there's one thing a lifetime studying physics teaches you... it's not that.
Episode 1 - The Bad Fish Paradigm
Penny opens up to a reluctant Sheldon after a less-than-stellar first date with Leonard, placing him in the uncomfortable position of having to keep a secret.
Episode 2 - The Codpiece Topology
The Codpiece Topology: Seeing Penny out on a date with another guy sends a distressed Leonard rushing back to Leslie Winkle, much to Sheldon's dismay.
Episode 3 - The Barbarian Sublimation
Penny becomes addicted to an online game based on the world of Conan the Barbarian and persistently pesters Sheldon for advice.
Episode 4 - The Griffin Equivalency
The Griffin Equivalency: Full of confidence after being named one of People Magazine's '30 to Watch under 30', Raj hits on Penny and becomes impossibly arrogant.
Episode 5 - The Euclid Alternative
The Euclid Alternative: When Leonard can't drive Sheldon to and from work, the friends stage an intervention to overcome Sheldon's fear of getting behind the wheel.
Episode 6 - The Cooper-Nowitzki Theorem
The Cooper-Nowitzki Theorem: Sheldon's friends are mystified when a younger student is attracted to him, but her intense devotion soon becomes too much.
Episode 7 - The Panty Piñata Polarization
After Sheldon bans Penny from the apartment for numerous minor infractions, she decides to retaliate. Her plan involves a telephone, and Sheldon's mother.
Episode 8 - The Lizard-Spock Expansion
A girl Wolowitz has a major crush on falls for Leonard, despite Wolowitz's elaborate attempts to woo her - including an abortive joyride on the Mars Rover.
Episode 9 - The White Asparagus Triangulation
The White Asparagus Triangulation: Sheldon is delighted that Leonard finally has a girlfriend matching his high standards... perhaps a little too delighted.
Episode 10 - The Vartabedian Conundrum
The Vartabedian Conundrum: Leonard goes to Penny for help when his relationship with Stephanie takes off faster than he'd like, but will he choose to act on her advice?
Episode 11 - The Bath Item Gift Hypothesis
The Bath Item Gift Hypothesis: At Christmas, Leonard's handsome colleague starts dating Penny, while Sheldon's obsession with gift-giving etiquette torments his friends.
Episode 12 - The Killer Robot Instability
The Killer Robot Instability: Kripke challenges the boys to a robot duel, while Howard is hurt when Penny reveals what she thinks about his behaviour towards women.
Episode 13 - The Friendship Algorithm
The Friendship Algorithm: Sheldon develops a scientific procedure for making friends when he discovers that Kripke has control of a new supercomputer at the university.
Episode 14 - The Financial Permeability
The Financial Permeability: When Sheldon lends Penny some money, it brings her ex-boyfriend Kurt back into her life, with negative consequences for the gang.
Episode 15 - The Maternal Capacitance
The Maternal Capacitance: A disastrous visit from Leonard's mother Beverly has the unexpected side-effect of bringing Leonard and Penny closer together.
Episode 16 - The Cushion Saturation
The Cushion Saturation: A game of paintball leads to a squabble when Penny accidentally shoots paint at one of Sheldon's cushions. Romance blossoms between Howard and Leslie.
Episode 17 - The Terminator Decoupling
The Terminator Decoupling: Leonard, Sheldon, Howard and Raj discover that beautiful sci-fi actress Summer Glau is on board their train to San Francisco.
Episode 18 - The Work Song Nanocluster
Penny's home-based business selling hair barrettes - her 'Pennyblossoms' - gets out of hand when a caffeine-high Sheldon takes charge.
Episode 19 - The Dead Hooker Juxtaposition
Penny develops a rivalry with sexy new female neighbour Alicia - who threatens to steal the boys' attention and become the 'new Penny'.
Episode 20 - The Hofstadter Isotope
The Hofstadter Isotope: Leonard is devastated when Stuart from the comic book shop chats Penny up. Even worse, she doesn't mind, so Sheldon tries to scupper the budding romance.
Episode 21 - The Vegas Renormalisation
Leonard and Raj take a heartbroken Howard to Las Vegas, home of slots, shrimp, and high-class hookers. Sheldon, meanwhile, is locked out of his apartment and forced to bunk with Penny.
Episode 22 - The Classified Materials Turbulence
The Classified Materials Turbulence: Things begin to look up for Leonard when Penny makes a surprising revelation on her second date with Stuart.
Episode 23 - The Monopolar Expedition
Leonard and Penny reconsider their feelings for each other, but then Leonard decides to spend the summer working at the North Pole - on a mission led by Sheldon.
The Big Bang Theory synopsis
Arch-nerds Leonard and Sheldon may know more than their fair share about subatomic particles, but when it comes to people in general, and women in particular, they're absolutely clueless...Episode Guide >
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