Hugh O'Brian

as Hugh Lombard

Shirley Eaton

as Ann Clyde

Fabian

as Mike Raven

Leo Genn

as General Mandrake

Stanley Holloway

as Det. William Henry Blore

Wilfrid Hyde-White

as Judge Arthur Cannon

Daliah Lavi

as Ilona Bergen

Dennis Price

as Dr. Edward Armstrong

Marianne Hoppe

as Elsa Grohmann

Mario Adorf

as Joseph Grohmann

Bill Mitchell

as Narrator (voice)

Christopher Lee

as Mr. U.N. Owen (voice)