When a break-in occurs at a secretive genetics institute, blind puzzle-maker Franco Arnò (Karl Malden: Patton, One-Eyed Jacks), who overheard an attempt to blackmail one of the institute's scientists shortly before the robbery, teams up with intrepid reporter Carlo Giordani (James Franciscus: Beneath the Planet of the Apes) to crack the case. But before long the bodies begin to pile up and the two amateur sleuths find their own lives imperilled in their search for the truth. And worse still, Lori (Cinzia De Carolis: Cannibal Apocalypse), Franco's young niece, may also be in the killer's sights...