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 2 Episode 20 - The Hofstadter Isotope

A fellow comic book enthusiast's hitting on Penny leads to Leonard and Howard going to a bar's Ladies' Night. Air Date : 13th-Apr-2009

Season 2 Episode 1 - The Bad Fish Paradigm

Penny's first date with Leonard goes awry; Penny finds Sheldon to be an unwilling confidant. Air Date : 22nd-Sep-2008  Read More

Season 2 Episode 2 - The Codpiece Topology

A jealous Leonard reacts to Penny's new guy by rebounding with Leslie. Air Date : 29th-Sep-2008  Read More

Season 2 Episode 3 - The Barbarian Sublimation

Sheldon creates a monster when he introduces Penny to online gaming. Air Date : 6th-Oct-2008  Read More

Season 2 Episode 4 - The Griffin Equivalency

Raj gets an inflated ego and makes a play for Penny after being referenced in a magazine article. Air Date : 13th-Oct-2008  Read More

Season 2 Episode 5 - The Euclid Alternative

Leonard and his friends stage an intervention to force Sheldon to face his fear of driving. Air Date : 20th-Oct-2008  Read More

Season 2 Episode 6 - The Cooper-Nowitzki Theorem

Sheldon and the gang are confused when a young grad student is attracted to him. Air Date : 3rd-Nov-2008  Read More

Season 2 Episode 7 - The Panty Piñata Polarization

When Sheldon bans Penny from the apartment for numerous minor infractions, she decides to retaliate. Air Date : 10th-Nov-2008  Read More

Season 2 Episode 8 - The Lizard-Spock Expansion

Leonard inadvertently steals away the new woman Wolowitz thinks is the love of his life. Air Date : 17th-Nov-2008  Read More

Season 2 Episode 9 - The White Asparagus Triangulation

Sheldon is thrilled when Leonard starts dating a woman who meets Sheldon's stringent standards. Air Date : 24th-Nov-2008  Read More

Season 2 Episode 10 - The Vartabedian Conundrum

Leonard asks Penny for advice when his new relationship starts moving too fast. Air Date : 8th-Dec-2008  Read More

Season 2 Episode 11 - 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. Air Date : 15th-Dec-2008  Read More

Season 2 Episode 12 - The Killer Robot Instability

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. Air Date : 12th-Jan-2009  Read More

Season 2 Episode 13 - The Friendship Algorithm

Sheldon creates a scientific procedure for making friends. Air Date : 19th-Jan-2009  Read More

Season 2 Episode 14 - The Financial Permeability

Sheldon's solution to Penny's financial difficulty leads to a confrontation between Leonard and Penny's ex-boyfriend. Air Date : 2nd-Feb-2009  Read More

Season 2 Episode 15 - The Maternal Capacitance

Leonard and Penny are drawn together after a disastrous visit from Leonard's mother. Air Date : 9th-Feb-2009  Read More

Season 2 Episode 16 - The Cushion Saturation

A paintball game leads to a fight between Sheldon and Penny, and romance for Leslie and Wolowitz. Air Date : 2nd-Mar-2009  Read More

Season 2 Episode 17 - 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. Air Date : 9th-Mar-2009  Read More

Season 2 Episode 18 - The Work Song Nanocluster

Penny's home business turns into a complete nightmare when Sheldon takes over. Air Date : 16th-Mar-2009  Read More

Season 2 Episode 19 - The Dead Hooker Juxtaposition

Penny squares off with a new beautiful female neighbor who may become the building's "new Penny." Air Date : 30th-Mar-2009  Read More

Season 2 Episode 20 - The Hofstadter Isotope

A fellow comic book enthusiast's hitting on Penny leads to Leonard and Howard going to a bar's Ladies' Night. Air Date : 13th-Apr-2009  Read More

Season 2 Episode 21 - The Vegas Renormalization

Leonard and Koothrappali escort a heartbroken Wolowitz to Las Vegas, and Sheldon becomes locked out of his apartment and must stay with Penny. Air Date : 27th-Apr-2009  Read More

Season 2 Episode 22 - 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. Air Date : 4th-May-2009  Read More

Season 2 Episode 23 - The Monopolar Expedition

The guys' plan to work over the summer at the North Pole makes Penny revaluate her feelings for Leonard. Air Date : 11th-May-2009  Read More