Lightman takes the leader of a self-help group to task on the episode "Beyond Belief." The latter is played by David Sutcliffe.
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The character played by David Sutcliffe believes he's helping people on Lie to Me. Lightman, however, thinks differently.
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As a self-help leader speaks on video, Lightman watches him in action in this scene. It's courtesy of the episode "Beyond Belief."
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Lie to Me Season 3 Episode 6 Quotes

What a load of old bollocks John. Your name is John, right?

Lightman

Lightman: John Stafford is responsible for your mom's suicide attempt.
Danielle: Are you asking or telling me?
Lightman: I am just telling you what you want to hear love.