Terence Morgan as Inspector Ralph Brown

Yolande Donlan as Jill Wilson

Anthony Oliver as Inspector Newcombe

André Morell as Robert Isaac Pitt

Reginald Beckwith as Harold

Ursula Howells as Antonia Pitt

Guido Lorraine as Pietr Revski

Basil Dignam as Wing Commander Riddle

Raymond Rollett as Sir Robert Rosper

Fred Johnson as Professor Robinson-Heston

Arnold Marlé as Karl Kopek

Mark Dignam as Prison Governor

John Horsley as Assistant Commissioner

Barry Lowe as Eric Colter

Diana Lambert as Young Woman

Petra Davies as Pitt's Maid (uncredited)

Brown Derby as Police Sergeant (uncredited)

Michael Godfrey as Chertwell Security Guard (uncredited)

Arthur Lovegrove as Nick (uncredited)

Louis Matto as Waiter (uncredited)

Guy Mills as Brown's Driver (uncredited)

Stuart Mitchell as Head Waiter (uncredited)

Jim Brady as Nick's Thug (uncredited)

Cyril Renison as Detective Sergeant Enders (uncredited)