John Mills as Superintendent Graham

Horst Buchholz as Korchinsky

Hayley Mills as Gillie

Yvonne Mitchell as Anya

Megs Jenkins as Mrs. Phillips

Anthony Dawson as Barclay

George Selway as Det. Sgt. Harvey

Shari as Christine

George Pastell as Poloma Captain

Paul Stassino as Poloma First Officer

Marne Maitland as Doctor

Meredith Edwards as Williams

Marianne Stone as Mrs. Williams

Rachel Thomas as Mrs. Parry

Brian Hammond as Dal Parry

Kenneth Griffith as Mr. Seymour

Eynon Evans as Mr Morgan

Christopher Rhodes as Inspector Bridges

Edward Cast as Det. Con. Thomas

David Davies as Desk Sergeant

Michael Anderson Jr. as Boy with Cap Gun (uncredited)

Harry Baird as Bridegroom (uncredited)

Tom Bowman as Seaman (uncredited)

Jim Brady as Pub Customer (uncredited)

Peter Halliday as Seaman (uncredited)

Hubert Hill as Policeman (uncredited)

Glyn Houston as Detective at Police Station (uncredited)

John Howard as Detective (uncredited)

Jack May as Mr Willis (uncredited)

Harry Phipps as Man in Bar (uncredited)

Stan Simmons as Referee (uncredited)

John Wilder as Police Line-Up (uncredited)