When Dr. Pieter Fales' patients start receiving ominous letters and getting murdered by an unknown black-clad assailant, he and his daughter both come under suspicion.

• The Cannon Group
• Golan-Globus Productions
• Klaus Kinski
• Donna Wilkes
• Marianna Hill
• Craig Wasson
• Richard Herd
• Joe Regalbuto
• Christopher Lloyd
• Flo Lawrence