Based on the true story of the hunt for the most savage and elusive serial killer on record. It started with eight bodies found murdered, raped and mutilated. A brilliant Soviet forensics expert (Stephen Rae) is put in charge of the case by his colonel (Donald Sutherland). But the investigation is buried under government red tape until a psychiatrist (Max von Sydow) is called in to create a psychological profile of the murder. With fifty-two victims to his name, the killer they call Citizen X finally takes shape before their eyes. But can they trap him before he kills again?