Jailed ex-cop Parker Barnes (Denzel Washington) gets a chance for redemption when he's freed to hunt down cyberspace escapee -- and virtual serial killer -- Sid 6.7 (Russell Crowe). Designed as a training tool for police, Sid possesses the traits of scores of mass murderers. As Barnes pursues his quarry, the personality of psycho Matthew Grimes -- who massacred the policeman's family -- emerges from Sid, and Barnes's quest turns into obsession.