face of death

A series of horrific murders are committed by a serial killer. At one of the crime scenes, police are shocked to find a picture of a masked figure leaving a message demanding that a specific officer investigate the case, or he will continue killing. Meanwhile, the "logic of the dead" (a reference to a figure who observes the events) intervenes, deciding to turn the tables. Why is the killer so insistent on choosing that particular officer? Will the officer be able to stop this madman? What is the secret behind the "logic of the dead"?