The Big Bang Theory

1The Bad Fish Paradigm

22 minSep 22, 2008★ 7.9

Penny's first date with Leonard goes awry; Penny finds Sheldon to be an unwilling confidant.

2The Codpiece Topology

21 minSep 29, 2008★ 7.7

A jealous Leonard reacts to Penny's new guy by rebounding with Leslie.

3The Barbarian Sublimation

21 minOct 6, 2008★ 8.0

Sheldon creates a monster when he introduces Penny to online gaming.

4The Griffin Equivalency

21 minOct 13, 2008★ 7.6

Raj gets an inflated ego and makes a play for Penny after being referenced in a magazine article.

5The Euclid Alternative

20 minOct 20, 2008★ 7.6

Leonard and his friends stage an intervention to force Sheldon to face his fear of driving.

6The Cooper-Nowitzki Theorem

21 minNov 3, 2008★ 7.9

Sheldon and the gang are confused when a young grad student is attracted to him.

7The Panty Piñata Polarization

21 minNov 10, 2008★ 8.0

When Sheldon bans Penny from the apartment for numerous minor infractions, she decides to retaliate.

8The Lizard-Spock Expansion

20 minNov 17, 2008★ 7.5

Leonard inadvertently steals away the new woman Wolowitz thinks is the love of his life.

9The White Asparagus Triangulation

21 minNov 24, 2008★ 7.5

Sheldon is thrilled when Leonard starts dating a woman who meets Sheldon's stringent standards.

10The Vartabedian Conundrum

21 minDec 8, 2008★ 7.0

Leonard asks Penny for advice when his new relationship starts moving too fast.

11The Bath Item Gift Hypothesis

21 minDec 15, 2008★ 8.3

Penny starts dating Leonard's handsome colleague; Leonard and his friends are tortured by Sheldon's obsession with gift-giving etiquette.

12The Killer Robot Instability

21 minJan 12, 2009★ 7.5

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.

13The Friendship Algorithm

21 minJan 19, 2009★ 7.5

Sheldon creates a scientific procedure for making friends.

14The Financial Permeability

21 minFeb 2, 2009★ 7.4

Sheldon's solution to Penny's financial difficulty leads to a confrontation between Leonard and Penny's ex-boyfriend.

15The Maternal Capacitance

21 minFeb 9, 2009★ 8.2

Leonard and Penny are drawn together after a disastrous visit from Leonard's mother.

16The Cushion Saturation

21 minMar 2, 2009★ 7.5

A paintball game leads to a fight between Sheldon and Penny, and romance for Leslie and Wolowitz.

17The Terminator Decoupling

21 minMar 9, 2009★ 7.5

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.

18The Work Song Nanocluster

20 minMar 16, 2009★ 7.6

Penny's home business turns into a complete nightmare when Sheldon takes over.

19The Dead Hooker Juxtaposition

20 minMar 30, 2009★ 7.6

Penny squares off with a new beautiful female neighbor who may become the building's "new Penny."

20The Hofstadter Isotope

20 minApr 13, 2009★ 7.6

A fellow comic book enthusiast's hitting on Penny leads to Leonard and Howard going to a bar's Ladies' Night.

21The Vegas Renormalization

22 minApr 27, 2009★ 7.5

Leonard and Koothrappali escort a heartbroken Wolowitz to Las Vegas, and Sheldon becomes locked out of his apartment and must stay with Penny.

22The Classified Materials Turbulence

19 minMay 4, 2009★ 7.5

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.

23The Monopolar Expedition

21 minMay 11, 2009★ 7.5

The guys' plan to work over the summer at the North Pole makes Penny revaluate her feelings for Leonard.