Season 2
The Big Bang Theory
23 EPISODES • 2008
This season, Leonard gets a girl. So does Sheldon. Howard drives the Mars Rover into a ditch. Raj woos a terminator. Gorgeous girl-next-door Penny falls under the spell of Age of Conan. And super-smart, ueberconfident Leslie Winkler reduces mere men to spineless jellyfish.

Season 1


1: The Bad Fish Paradigm
Sep 22, 2008
Penny's first date with Leonard goes awry; Penny finds Sheldon to be an unwilling confidant.
2: The Codpiece Topology
Sep 29, 2008
A jealous Leonard reacts to Penny's new guy by rebounding with Leslie.
3: The Barbarian Sublimation
Oct 6, 2008
Sheldon creates a monster when he introduces Penny to online gaming.
4: The Griffin Equivalency
Oct 13, 2008
Raj gets an inflated ego and makes a play for Penny after being referenced in a magazine article.
5: The Euclid Alternative
Oct 20, 2008
Leonard and his friends stage an intervention to force Sheldon to face his fear of driving.
6: The Cooper-Nowitzki Theorem
Nov 3, 2008
Sheldon and the gang are confused when a young grad student is attracted to him.
7: The Panty Piñata Polarization
Nov 10, 2008
When Sheldon bans Penny from the apartment for numerous minor infractions, she decides to retaliate.
8: The Lizard-Spock Expansion
Nov 17, 2008
Leonard inadvertently steals away the new woman Wolowitz thinks is the love of his life.
9: The White Asparagus Triangulation
Nov 24, 2008
Sheldon is thrilled when Leonard starts dating a woman who meets Sheldon's stringent standards.
10: The Vartabedian Conundrum
Dec 8, 2008
Leonard asks Penny for advice when his new relationship starts moving too fast.
11: The Bath Item Gift Hypothesis
Dec 15, 2008
Penny starts dating Leonard's handsome colleague; Leonard and his friends are tortured by Sheldon's obsession with gift-giving etiquette.
12: The Killer Robot Instability
Jan 12, 2009
Penny's criticism of Wolowitz's romantic life pushes him into depression and AWOL for a fighting robot battle the rest of guys are depending on him for.
13: The Friendship Algorithm
Jan 19, 2009
Sheldon creates a scientific procedure for making friends.
14: The Financial Permeability
Feb 2, 2009
Sheldon's solution to Penny's financial difficulty leads to a confrontation between Leonard and Penny's ex-boyfriend.
15: The Maternal Capacitance
Feb 9, 2009
Leonard and Penny are drawn together after a disastrous visit from Leonard's mother.
16: The Cushion Saturation
Mar 2, 2009
A paintball game leads to a fight between Sheldon and Penny, and romance for Leslie and Wolowitz.
17: The Terminator Decoupling
Mar 9, 2009
Leonard, Sheldon and Wolowitz are ecstatic to learn that a famous science-fiction actress (Summer Glau) is on board the train they are taking to San Francisco.
18: The Work Song Nanocluster
Mar 16, 2009
Penny's home business turns into a complete nightmare when Sheldon takes over.
19: The Dead Hooker Juxtaposition
Mar 30, 2009
Penny squares off with a new beautiful female neighbor who may become the building's "new Penny."
20: The Hofstadter Isotope
Apr 13, 2009
A fellow comic book enthusiast's hitting on Penny leads to Leonard and Howard going to a bar's Ladies' Night.
21: The Vegas Renormalization
Apr 27, 2009
Leonard and Koothrappali escort a heartbroken Wolowitz to Las Vegas, and Sheldon becomes locked out of his apartment and must stay with Penny.
22: The Classified Materials Turbulence
May 4, 2009
Penny's second date with Stuart sees her making a comment that gives Leonard new hope for a relationship with her. Wolowitz realizes there's a crucial error in a NASA project he's working on.
23: The Monopolar Expedition
May 11, 2009
The guys' plan to work over the summer at the North Pole makes Penny revaluate her feelings for Leonard.
Season 3
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