Check out highlights from The Big Bang Theory Season 6 in this video. It debuted at Comic-Con 2013.
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The Big Bang Theory Season 6 Quotes

Raj: Okay, here's another one: if a zombie bites a vampire, and the vampire bites a human, does the human become a vampire or a zombie? Or, a zompire?

Sheldon: Lipid residue. An anal autograph. A colon calling card, if you will.
Cleaner: Tuesday okay?