Suspect

Tony Britton

as

Dr. Robert Mar...

Virginia Maske...

as

Dr. Lucy Byrne

Ian Bannen

as

Alan Andrews

Kenneth Griffi...

as

Dr Shole

Peter Cushing

as

Professor Sewe...

Thorley Walters

as

Special Agent ...

Donald Pleasen...

as

Parsons, alias...

Spike Milligan

as

Arthur, lab or...

Raymond Huntley

as

Sir George Gat...

Sam Kydd

as

Slater

Anthony Booth

as

Parkin

Basil Dignam

as

Dr Childs

Brian Oulton

as

Director

Robert Bruce

as

Levers

John Payne

as

Iverson

Bruce Wightman

as

Phil the Barman

Geoffrey Bayld...

as

Rosson

Andre Charisse

as

Heller

Ian Wilson

as

Pin Table Man

Margaret Lacey

as

Prince's Secre...

Murray Melvin

as

Teddy Boy