A nonverbal autistic boy stumbles upon a teenage heiress who has been kidnapped by a trio of young psychopaths, who are intent on extorting diamonds from her stepfather.
Walt Sherill is attacked and beat down by a group of juvenile delinquents on his way home from work one night. The boys who attacked him are not previously known by the police and are therefore hard to track down. As Sherill starts getting impatient he begins his own investigation. Meanwhile, Detective Sergeant Koleski does his best to track down the culprits.
A bitter young man sets out to get back at the gangsters who murdered his father.
When several women are found mutilated and murdered, the Paris police are baffled as to who the killer may be. All evidence points to Dupin, but soon it becomes apparent that it is someone (or something) stronger and deadlier than a human.