Sam Tyler receives a mysterious phone call that leads to a headless body. Simultaneously Lt. Hunt finds a severed head delivered in a gift box to the precinct, which sets off the discovery of a chain of bizarre decapitations. Meanwhile, Ray's ne'er-do-well brother, Eddie, may be entangled with the murders, but the peculiar situation leads the 1-2-5 to a biker, a Wall Street bigwig and a terribly disfigured man. As Sam, Hunt and the rest of the detectives sort out these hideous crimes, Ray makes a life-changing decision, and Sam makes an extraordinary discovery about the original tipster phone call.