Brennan inspects a doomsday bunker that becomes part of her investigation on Bones. "The Doom in the Gloom" is the 19th episode of the show's eighth season.
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Bones Season 8 Episode 19 Quotes

Bones: Certain is an absolute, Ms. Wick. You can't be mostly certain.
Cam: Mostly certain's good for me.

Cam: Found the head! In the toilet.
Booth: Okay, that's a rough way to be remembered.