Dr. Cal Lightman teaches a course in body language and makes an honest fortune exploiting it. He's employed by various public authorities in various investigations, doing more when the police etc. fail to go the extra mile. So he can afford to constitute a team of his own, which like clients and others has to put up with his mind-games.
Did You Know?
Most of the actors went on a micro-expressions course before they started filming the show - for preparation. Except for Tim Roth, who avoided learning most of the actual science because he didn't want it affecting his relationships with his family and friends. He'd seen what it can do from the show. See more
Dr. Cal Lightman
Now that's the truth.