A secret about Gillian's past is uncovered on the episode "Sweet Sixteen." This clips gives us an idea of what that is.
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Watch the full episode of Lie To Me's "Beat the Devil" which returned to FOX.
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This is the official Fox promo for "Honey." Garrett Dillahunt guest stars on the episode.
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Lie to Me Quotes

Here's the problem, Martin Walker is a psychopath and probably a killer. Just though you should know.

Cal Lightman

Martin Walker: A good chess player thinks five moves ahead.
Cal Lightman: Great chess players only think one move ahead, but it's always the right move.