Offender profiler Frank Black, a member of the private investigative organisation Millennium Group, retires to Seattle with his family after a breakdown caused him to quit working for the Federal Bureau of Investigation. Using his incredible profiling skills, Black helps in an effort to catch a vicious murderer who believes he is fulfilling apocalyptic prophecies.

Offender profiler Frank Black, a member of the private investigative organisation Millennium Group, is sent to San Francisco to track down a doomsday cult which murders its brainwashed members when they disobey it.

Frank travels to Weber County, Utah, where he meets with Prosecutor Calvin Smith. The District Attorney's office convicted Sheriff William Garry of murdering his wife and three children. Garry had confessed to the crime, and his fingerprints were found on the murder weapon, a tool used for carving wood. Now all that remains is for the jury to decide if Garry should receive the death penalty. Smith hopes Frank can develop a psychological profile that will leave no doubt in the jury's mind that Garry is a cold, calculating murderer.