Laurence Payne
— Norman Martell
Patricia Dainton
— Helen Martell
Jane Griffiths
— Peggy Hill
Edward Underdown
— Dr. Peter Murdoch
John Arnatt
— Supt. Ross
Humphrey Lestocq
— Simmons, the Producer
Lucy Griffiths
— Miss Potter
Olive Milbourne
— Mrs. Booth
Arthur Hewlett
— Marshall
Annette Kerr
— Cinema cashier
Cleo Laine
— Cleo
Dudley Moore
— Rehearsal Pianist (Uncredited)
Sylvia Davis
— Cinema sales girl (uncredited)
Max Faulkner
— Det. Sgt. Fred Smith (uncredited)
Garard Green
— Patrol car policeman (uncredited)
Arthur Howell
— P.C. Williams (uncredited)
Richard Neller
— Sleeping Man in Theater (uncredited)
Pat Ryan
— Detective Examining Tape-Recorder (uncredited)
Stuart Saunders
— Cinema manager (uncredited)
Arthur Skinner
— Det. Sgt. Carter (uncredited)
John Tatham
— Detective / Fingerprints Officer (uncredited)