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
When Leonard, Sheldon, Raj and Wolowitz return from the Renaissance Fair, they witness that Penny has started seeing a new guy. Jealous and lonely, Leonard tries to get together with physicist Leslie Winkle, Sheldon's arch-enemy.
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
Full of confidence following being named one of People Magazine's "30 to Watch Under 30", Raj becomes impossibly arrogant. Everyone - except Sheldon - does their best to be supportive, but it's the final straw for Leonard when Raj hits on Penny.
Episode 5 - The Euclid Alternative
When Leonard starts working late at the lab, he's not able to drive Sheldon into work. Terrified of driving, Sheldon pesters Penny and the others for lifts - creating such an annoyance that the gang decide it's time for an intervention.
Episode 6 - The Cooper-Nowitzki Theorem
When an obsessive grad student named Ramona takes a shine to Sheldon, she quickly becomes his assistant - and shortly after - his girlfriend. At first she seems like a positive influence, but she soon starts taking over - banning Shedlon from Halo, comic books, and paintball, and eventually attempting to take credit for Sheldon's discoveries...
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
Sheldon is delighted that Leonard finally has a girlfriend matching his high standards, or in his words, a "McCoy" to their "Kirk" and "Spock". In fact, he's so pleased at Leonard's pairing with Stephanie that he can't resist doing everything in his power to help their relationship flourish...
Episode 10 - The Vartabedian Conundrum
Leonard seeks Penny's counsel when his relationship with Stephanie takes off faster than he'd like. Meanwhile, Sheldon has a ringing in his ears, and despite exhaustive attempts at finding a solution, it won't go away.
Episode 11 - The Bath Item Gift Hypothesis
Leonard gets the opportunity to work with award-winning scientist David Underhill. He's intelligent, cool, smart and handsome - which soon renders Leonard jealous when he takes an interest in Penny. Meanwhile, Sheldon must devise a means of reciprocating Penny's Christmas gift.
Episode 12 - The Killer Robot Instability
Following comments from Penny about the desperate state of his love life, Wolowitz decides that he's too depressed to help the others in an upcoming robot fighting competition. Sheldon accepts a challenge from his colleague Barry Kripke, so their robotic creations are pitted against each other in a one-on-one duel to the death.
Episode 13 - The Friendship Algorithm
When Sheldon requires the use of a computer in Barry Kripke's office, Sheldon faces a problem - only Barry's friends are welcome - so that excludes him. However, with the aid of a friendship flowchart of his own design, Sheldon thinks he's on course to becoming one of his former enemy's pals.
Episode 14 - The Financial Permeability
When Penny struggles to pay her rent, she borrows money from Sheldon. While Sheldon has little doubt in his mind that she will pay him back, Penny fears that she will be in Shedlon's debt forever. But thanks to an heroic effort from Leonard - which involves a run-in with Penny's ex, Kurt - Penny is able repay the loan.
Episode 15 - The Maternal Capacitance
When Dr Beverly Hofstadter, a sucessful psychiatrist and neuroscientist - and Leonard's mother - comes to visit, her constant character analyses leave Penny in tears and Leonard thoroughly embarrassed. However, the turmoil brings Leonard and Penny closer together - very close, in fact. All Leonard has to do is not screw things up. And that's a tall order.
Episode 16 - The Cushion Saturation
Tragedy strikes when a game of paintball gets ugly - Penny shoots Sheldon's special cushion, leaving an ugly green stain. But although misfortune plagues Sheldon, Howard's luck changes - sort of - when Leslie Winkle becomes his girlfriend.
Episode 17 - The Terminator Decoupling
On a train to San Francisco, Leonard, Sheldon, Wolowitz and Raj discover that beautiful sci-fi actress Summer Glau is on board. Howard begins formulating a plan to seduce her, but he's beaten to the post by a Raj - who's drunk on non-alcoholic beer. Things look promising until Howard instructs him to check the label.
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
Leonard is devastated when geeky comic store clerk Stuart hits on Penny... successfully. Meanwhile, Raj and Wolowitz embark on a mission to seduce attractive girls by attending a 'ladies' night' at a local bar.
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
Sheldon discovers the merits of toilet humour after Howard's zero-gravity poop chute leaves some astronauts in a sticky situation. Meanwhile, Stuart embarks on his second date with Penny - but not before asking Leonard for advice.
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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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…