Lie Detector is a psychological thriller centering on David Wellman, an avid rock climber, family man and FBI agent who suffers a traumatic brain injury that renders him unable to use or understand speech, yet heightens his ability to recognize deception. With his best friend, fellow agent Spence McKenzie, David puts his new skills to the test by investigating a hate crime and tracking down a suspected double agent. But seeing dishonesty all around him, David soon begins to self-destruct, then chooses a journey of redemption that redefines his concept of honesty, trust and family.