The day before he retires, Seattle police detective Jake Riley almost captures The Torch, a notorious serial killer who preys on single women. After this incident, Riley is offered a job with the National Security Force. They take Riley to a top-secret science lab, where they have cloned an exact copy of the Torch from a sample of his DNA. The clone, called Replicant, shares Torch's physique as well as his telepathic abilities. As the Torch's genetic double, Replicant can instinctively lead the authorities to his other half. But before Replicant can be used effectively, he needs to be taught simple human behavior, such as speech and movement. Riley is assigned to look after Replicant and train him on the streets of the city. But when it comes time to set Replicant loose on the trail of the Torch, Riley can't be sure whose side this genetic clone will ultimately be on.