Michael York

Geoffrey Richter-Douglas

Elke Sommer

Erika Altschul

Peter Carsten

Major Tauntler

Marius Goring

Professor Christian Altschul

Anton Diffring

Colonel Hirsch

Andrew Keir

Von Gorian

Rupert Davies

Captain Whitney

Alexandra Stewart

Stephanie

William Marlowe

Anderson

Alan Rothwell

Brandner

Richard Hurndall

Blinker Hall

Michael Robbins

Cockney Sergeant

Ben Howard

Jamie Fergusson

Arnold Diamond

Major Proudfoot

Clive Morton

Lord Delford

Gary Waldhorn

Harlich

Ronald Adam

Prime Minister

Frazer Hines

Radio Operator

Ruth Kettlewell

Mrs. Parker

Ray Lonnen

Sgt. Grant

Dorian Healy

Child (uncredited)