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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The Big Bang Theory Season 4 Episode 7 Quotes

I believe you were about to ask me to choose a cocktail. Fortunately, thanks to computer-savvy alcoholics, there's an app for that.

Sheldon

Raj: Woh, woh, woh! I don't want to speak to the FBI.
Leonard: Why not?
Raj: I'm brown and I talk funny.