Grissom announces to his team that he is leaving CSI. But there is one case to solve. Brass has him enroll in a college classroom where a serial killer is being interviewed through closed circuit television. He is a cold monster who loves frightening the regular students. He seems to have no soul but knows how to play the game. There is a surprising discovery at the end. A part of this episode is the team having to deal with Gil's leaving. There are some touching scenes.
