2x01 The Bad Fish Paradigm
September 22, 2008 8:00 pm
Penny's first date with Leonard goes awry; Penny finds Sheldon to be an unwilling confidant.
2x02 The Codpiece Topology
September 29, 2008 8:00 pm
A jealous Leonard reacts to Penny's new guy by rebounding with Leslie.
2x03 The Barbarian Sublimation
October 6, 2008 8:00 pm
Sheldon creates a monster when he introduces Penny to online gaming.
2x04 The Griffin Equivalency
October 13, 2008 8:00 pm
Raj gets an inflated ego and makes a play for Penny after being referenced in a magazine article.
2x05 The Euclid Alternative
October 20, 2008 8:00 pm
Leonard and his friends stage an intervention to force Sheldon to face his fear of driving.
2x06 The Cooper-Nowitzki Theorem
November 3, 2008 8:00 pm
Sheldon and the gang are confused when a young grad student is attracted to him.
2x07 The Panty Piñata Polarization
November 10, 2008 8:00 pm
When Sheldon bans Penny from the apartment for numerous minor infractions, she decides to retaliate.
2x08 The Lizard-Spock Expansion
November 17, 2008 8:00 pm
Leonard inadvertently steals away the new woman Wolowitz thinks is the love of his life.
2x09 The White Asparagus Triangulation
November 24, 2008 8:00 pm
Sheldon is thrilled when Leonard starts dating a woman who meets Sheldon's stringent standards.
2x10 The Vartabedian Conundrum
December 8, 2008 8:00 pm
Leonard asks Penny for advice when his new relationship starts moving too fast.
2x11 The Bath Item Gift Hypothesis
December 15, 2008 8:00 pm
Penny starts dating Leonard's handsome colleague; Leonard and his friends are tortured by Sheldon's obsession with gift-giving etiquette.
2x12 The Killer Robot Instability
January 12, 2009 8:00 pm
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.
2x13 The Friendship Algorithm
January 19, 2009 8:00 pm
Sheldon creates a scientific procedure for making friends.
2x14 The Financial Permeability
February 2, 2009 8:00 pm
Sheldon's solution to Penny's financial difficulty leads to a confrontation between Leonard and Penny's ex-boyfriend.
2x15 The Maternal Capacitance
February 9, 2009 8:00 pm
Leonard and Penny are drawn together after a disastrous visit from Leonard's mother.
2x16 The Cushion Saturation
March 2, 2009 8:00 pm
A paintball game leads to a fight between Sheldon and Penny, and romance for Leslie and Wolowitz.
2x17 The Terminator Decoupling
March 9, 2009 8:00 pm
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.
2x18 The Work Song Nanocluster
March 16, 2009 8:00 pm
Penny's home business turns into a complete nightmare when Sheldon takes over.
2x19 The Dead Hooker Juxtaposition
March 30, 2009 8:00 pm
Penny squares off with a new beautiful female neighbor who may become the building's "new Penny."
2x20 The Hofstadter Isotope
April 13, 2009 8:00 pm
A fellow comic book enthusiast's hitting on Penny leads to Leonard and Howard going to a bar's Ladies' Night.
2x21 The Vegas Renormalization
April 27, 2009 8:00 pm
Leonard and Koothrappali escort a heartbroken Wolowitz to Las Vegas, and Sheldon becomes locked out of his apartment and must stay with Penny.
2x22 The Classified Materials Turbulence
May 4, 2009 8:00 pm
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.
2x23 The Monopolar Expedition
May 11, 2009 8:00 pm
The guys' plan to work over the summer at the North Pole makes Penny revaluate her feelings for Leonard.
