Episode Titles: Extract
You are viewing a list of 1 The Big Bang Theory episode featuring "Extract" in their title.
Season 6, Episode 6 - The Extract Obliteration
Aired November 1, 2012
Penny has started taking a history class at the local college but she doesn't want Leonard to know. Meanwhile, Sheldon worries about his friendship with Stephen Hawking after a game of "Words with Friends".