Dr. Cal Lightman runs into a pretty big problem on Monday's new episode of Lie to Me.

He's hired by a terminally ill man and tasked with tracking down his daughter's killer. It's the man's dying wish.

But during the investigation, Lightman starts to suspect the client's sons could be involved in the crime. Uh-oh. What's a doctor to do in this situation? Watch the official Fox promo for "Smoked" now:

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