Free-lance undercover agent Coplan receives a phone call from an old girlfriend in Turkey. The panic-stricken woman gives sketchy details of a plot that threatens world security. When Coplan arrives, he is told the woman has been killed, and the trail of the murderer leads to her mad-scientist brother.

• Comptoir Français du Film Production (CFFP)
• Cinesecolo
• Claudio Brook
• Margaret Lee
• Klaus Kinski
• Jean Servais
• Jean Topart
• Bernard Blier
• Hans Meyer
• Nanna Michael