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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...

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

    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

    Episode 2 - 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

    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

    Episode 4 - 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

    Episode 5 - 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

    Episode 6 - 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

    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

    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

    Episode 9 - 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

    Episode 10 - 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

    Episode 11 - 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

    Episode 12 - 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

    Episode 13 - 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

    Episode 14 - 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

    Episode 15 - 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

    Episode 16 - 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

    Episode 17 - 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

    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

    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

    Episode 20 - 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

    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

    Episode 22 - 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

    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.