Koothrappali is living in a fantasy world. It's bad because he's dancing there with his best friend's gal.
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Former basketball player Rick Fox is seen here on The Big Bang Theory. It's a scene from the episode "The Love Car Displacement."
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Leonard gets an idea for a smart phone app on the first Big Bang episode of 2011. This is a shot from the opening scene.
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The group goes all Justice League in this scene/episode of The Big Bang Theory. Seems about right for the show, doesn't it?
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A picture of Sheldon's love interest, Amy Farrah Fowler, on The Big Bang Theory.
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Sorry, it's not the best picture, but here's a photo of Bernadette from The Big Bang Theory.
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Penny, Bernadette and Amy are seen here during a night out. It's a scene from the episode "The Alien Parasite Hypothesis."
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Yes, that's Keith Carradine on The Big Bang Theory. He's played the character of Penny's dad.
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Wil Wheaton returns to The Big Bang Theory on the episode "The 21-Second Excitation." He once again causes problems for the fellas.
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Welcome to comedy, Eliza Dushku. The actress appears as a FBI agent on The Big Bang Theory episode "The Apology Insufficiency."
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Eliza Dushku guest stars on the November 4 episode of The Big Bang Theory. She plays a federal agent.
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Leonard tries to keep an affair secret from Sheldon on "The Irish Pub Formulation." This is a scene from that episode.
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TBBT Quotes

I just gave you my virginity, woman. Cool your jets!

Sheldon

(Singing) Thor and Dr Jones, Thor and Dr. Jones. One plays with lightening, the other plays with bones.

Howard and Raj