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The Big Bang Theory Season 2 Episodes
Season 2 Episode Guide
23 Episodes 2008 - 2009
The second season begins with Leonard (Johnny Galecki) and Penny (Kaley Cuoco) returning from their first date, but things don't work out exactly as planned. Meanwhile, despite becoming even more obsessive and neurotic, Sheldon (Jim Parsons) strikes up an unusual friendship with Penny. Sara Gilbert has a recurring character arc as a fellow scientist who's interested in Leonard; and memorable guest cameos include Charlie Sheen, Summer Glau and George Smoot. Simon Helberg and Kunal Nayyar also star.
Episode 1
The Bad Fish Paradigm
Mon, Sep 22, 2008 30 mins
In the second-season opener, Penny surprisingly turns to Sheldon as a confidant after her disastrous first date with Leonard. Mrs. Wolowitz: Carol Ann Susi.
Episode 2
The Codpiece Topology
Mon, Sep 29, 2008 30 mins
A jealous Leonard reacts to Penny's new guy by rebounding with Leslie (Sara Gilbert). Eric: Travis Schuldt.
Episode 3
The Barbarian Sublimation
Mon, Oct 6, 2008 30 mins
Sheldon shows Penny the joys of online gaming, creating an addict in the process. Gablehauser: Mark Harelik. Blaine: Tyler Olson. Tom: Mark Hames.
Episode 4
The Griffin Equivalency
Mon, Oct 13, 2008 30 mins
Raj gets an ego boost after winning some fame from a magazine article and risks his friendship with Leonard by trying to win over Penny.
Episode 5
The Euclid Alternative
Mon, Oct 20, 2008 30 mins
The friends band together to help Sheldon face his fear of driving. Octavia: Octavia Spencer. Lourdes: Livia Trevino.
Episode 6
The Cooper-Nowitzki Theorem
Mon, Nov 3, 2008 30 mins
The gang is puzzled by a young grad student's attraction to Sheldon. Ramona: Riki Lindhome. Kathy: Emily Happe.
Episode 7
The Panty Piñata Polarization
Mon, Nov 10, 2008 30 mins
It's an all-out war between Penny and Sheldon when he bans her from the apartment for what she thinks are petty infractions.
Episode 8
The Lizard-Spock Expansion
Mon, Nov 17, 2008 30 mins
A smitten Wolowitz thinks he's found his soul mate, until the woman meets Leonard.
Episode 9
The White Asparagus Triangulation
Mon, Nov 24, 2008 30 mins
Sheldon is ecstatic when Leonard begins dating Stephanie, who meets all of Sheldon's seemingly impossible standards.
Episode 10
The Vartabedian Conundrum
Mon, Dec 8, 2008 30 mins
Leonard's relationship with Stephanie is moving too fast for him, so he runs to Penny for advice.
Episode 11
The Bath Item Gift Hypothesis
Mon, Dec 15, 2008 30 mins
Christmas brings no tidings of comfort and joy to Leonard, whose colleague starts dating Penny. Meanwhile, Sheldon drives everyone crazy over his adherence to gift-giving etiquette.
Episode 12
The Killer Robot Instability
Mon, Jan 12, 2009 30 mins
Penny wounds Wolowitz with a comment about his love life, prompting him to abandon friends who need him for a fighting-robot contest.
Episode 13
The Friendship Algorithm
Mon, Jan 19, 2009 30 mins
Here's a conundrum to baffle the guys: Sheldon's intelligence, which renders him socially awkward, is also the source of his new scientific procedure for making friends.
Episode 14
The Financial Permeability
Mon, Feb 2, 2009 30 mins
Sheldon helps Penny with a financial crisis, but his solution leads to a confrontation between Leonard and Penny's burly ex-boyfriend Kurt.
Episode 15
The Maternal Capacitance
Mon, Feb 9, 2009 30 mins
Leonard suffers through a dreadful visit from his mother that ends up bringing him and Penny closer.
Episode 16
The Cushion Saturation
Mon, Mar 2, 2009 30 mins
A paintball game has Penny and Sheldon engaging in their own personal battle and Leslie and Wolowitz finding romance.
Episode 17
The Terminator Decoupling
Mon, Mar 9, 2009 30 mins
The guys' trip to San Francisco takes a detour once they learn that actress Summer Glau is on their train.
Episode 18
The Work Song Nanocluster
Mon, Mar 16, 2009 30 mins
Penny starts a hair-product business that suffers when her friends, particularly Sheldon, become involved.
Episode 19
The Dead Hooker Juxtaposition
Mon, Mar 30, 2009 30 mins
Penny develops a rivalry with a pretty woman who moves into the building.
Episode 20
The Hofstadter Isotope
Mon, Apr 13, 2009 30 mins
Penny is romanced by a friend of the guys' while at a comic-book store. Meanwhile, Leonard and Wolowitz search for love at a bar's ladies' night.
Episode 21
The Vegas Renormalization
Mon, Apr 27, 2009 30 mins
Leonard, Koothrappali and Wolowitz go to Las Vegas, and Sheldon is locked out of the apartment, leaving him no choice but to stay with Penny.
Episode 22
The Classified Materials Turbulence
Mon, May 4, 2009 30 mins
While on a date with Stuart, Penny makes an unexpected discovery regarding Leonard; and Wolowitz asks for his friends' help on his NASA project when he uncovers a design flaw.
Episode 23
The Monopolar Expedition
Mon, May 11, 2009 30 mins
In the second-season finale, Leonard gets ready for a three-month long science trip, and he and Penny come to terms with their feelings for each other.
