Who is behind a dangerous radio frequency? And why? Those questions are at the center of this Fringe episode, as previewed in this video.
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Fringe Season 3 Episode 6 Quotes

Peter: I had to go back, I forgot to say skim.
Bolivia: You walked there twice? You didn't have to do that.
Peter: I had a motive. It's the little things that make me irresistible.

Great human destruction, I guess we'll have to hope for the former.

Walter