Cast
- Robert Vaughn as Bill Fenner
- Elke Sommer as Sandra Fane
- Felicia Farr as Claire Connor
- Karlheinz Böhm as Robert Wahl
- Luciana Paluzzi as Giulia Almeranti
- Boris Karloff as Dr. Pierre Vaugiroud
- Roger C. Carmel as Mike Ballard
- Edward Asner as Frank Rosenfeld
- Joe De Santis as Jan Aarvan
- Fabrizio Mioni as Russo
Crew
- Jerry Thorpe · Director
- E. Jack Neuman · Writer
- Helen MacInnes · Writer
- E. Jack Neuman · Producer
- Jerry Thorpe · Producer
- Lalo Schifrin · Composer
- Milton R. Krasner · Cinematographer
- Henry Berman · Editor