Patrick Holt

Character: Inspector Gregory

Emrys Jones

Character: Howard Rogers

Honor Blackman

Character: Ann Rogers

Bruce Beeby

Character: Det. Sgt Conway

John Horsley

Character: Mr. Fisher

Robert Perceval

Character: Bank Manager

Wally Patch

Character: Barman

Frank Pettitt

Character: Fred (as Frank Pettit)

Benedicta Leigh

Character: Policewoman Scott

Peter Glaze

Character: Station Booking Clerk

Vi Stevens

Character: Landlady

Howard Greene

Character: River Police Sergeant

Raymond Smith

Character: River Police Constable

Lawrence James

Character: Uniformed Constable

Reginald Hearne

Character: Doctor (as Reggie Hearne)

Barry Linehan

Character: Forensic Chemist

Gerry Duggan

Character: Norman Cole

Colin Rix

Character: Plain Clothes Detective

Bill Mills

Character: Photographer

Pat Shaw

Character: Uniformed Policewoman

John Tatham

Character: PC Barrow (uncredited)