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 don't like the Olive Garden. They treat me like family.

Sheldon

Wolowitz: You love that spot.
Sheldon: No, I love my mother. My feelings for my spot are much greater. It is the singular location in space around which revolves my entire universe. And now it's yours.