There is no need for a lie detector, no need for hard evidence, and even no need for sound. In most cases, Dr. Carl Lightman (played by Tim Roth) can judge whether a person is lying or not just by the slightest change in expression. This is the superb skill of Dr. Carl Lightman (played by Tim Roth). Dr. Lightman works for a private institution that specializes in the study of micro-expressions and has absolute authority in judging lies. When the FBI, the police, or private institutions encounter unresolved issues, it is a good time for Dr. Lightman and his team to show their skills. With their rich experience and cautious style, they expose lies one after another and restore the truth. In front of them, no liar can hide. This film is adapted from a true story.