E21 • The Vegas Renormalization

E1 • The Bad Fish Paradigm

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

21m • 2008

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

E2 • The Codpiece Topology

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

20m • 2008

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

E3 • The Barbarian Sublimation

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

20m • 2008

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

E4 • The Griffin Equivalency

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

20m • 2008

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

E5 • The Euclid Alternative

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

19m • 2008

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

E6 • The Cooper-Nowitzki Theorem

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

20m • 2008

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

E7 • The Panty Piñata Polarization

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

20m • 2008

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

E8 • The Lizard-Spock Expansion

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

19m • 2008

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

E9 • The White Asparagus Triangulation

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

20m • 2008

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

E10 • The Vartabedian Conundrum

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

20m • 2008

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

E11 • The Bath Item Gift Hypothesis

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

20m • 2008

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

E12 • The Killer Robot Instability

Penny's criticism of Wolowitz's romantic life pushes him into depression and he goes AWOL for a fighting robot battle the rest of guys are depending on him for.

20m • 2008

Penny's criticism of Wolowitz's romantic life pushes him into depression and he goes AWOL for a fighting robot battle the rest of guys are depending on him for.

E13 • The Friendship Algorithm

Sheldon creates a scientific procedure for making friends.

20m • 2008

Sheldon creates a scientific procedure for making friends.

E14 • The Financial Permeability

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

21m • 2008

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

E15 • The Maternal Capacitance

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

20m • 2008

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

E16 • The Cushion Saturation

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

20m • 2008

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

E17 • The Terminator Decoupling

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.

20m • 2008

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.

E18 • The Work Song Nanocluster

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

20m • 2008

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

E19 • The Dead Hooker Juxtaposition

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

19m • 2008

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

E20 • The Hofstadter Isotope

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

19m • 2008

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

E21 • The Vegas Renormalization

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

21m • 2008

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

E22 • The Classified Materials Turbulence

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.

18m • 2008

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.

E23 • The Monopolar Expedition

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

20m • 2008

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