Demonstrating that a little knowledge is a dangerous thing, a convicted strangler studies the paranormal and finds a way to render himself invisible. Once he escapes, he sets out to find and eliminate five women who remind him of the mother he murdered. A police lieutenant sets out to safeguard them and bring the invisible killer to justice.

• Jordan/Lyon Productions Ltd.
• Robert Foxworth
• Stefanie Powers
• Sue Lyon
• Mark Slade
• Leslie Parrish
• Marianna Hill
• Elke Sommer
• Percy Rodriguez