Dr. Hawley Harvey Crippen

Donald Pleasence

Belle Crippen

Coral Browne

Ethel Le Neve

Samantha Eggar

R.D. Muir (as Sir Donald Wolfit)

Donald Wolfit

Captain McKenzie

James Robertson Justice

Mr. Tobin

Geoffrey Toone

Lord Chief Justice

Oliver Johnston

Chief Inspector Dew

John Arnatt

Clerk of the Court

Edward Ogden

Dr. Pepper

Douglas Bradley-Smith

Mrs. Clara Arditti

Olga Lindo

Mrs. Jackson

Elspeth March

Bruce Martin

Paul Carpenter

Mr. Arditti

Basil Henson

Harry

John Lee

Prison Governor

Edward Underdown

Mrs. Stratton

Betty Bascombe

Dr. Rogers

Hamilton Dyce

Sgt. Mitchell

Basil Beale

Miss Curnow

Totti Truman Taylor

Harding

Edward Cast

Howlett

Ian Whittaker

Chemist

Colin Rix

Police Sergeant Outside Courtroom (uncredited)

Terence Brook

Defence QC Clerk (uncredited)

Eric Dodson

Mrs. Stratton

Betty Baskcomb

Radio Officer Andrews (uncredited)

Max Faulkner

Ships Steward (uncredited)

Guy Standeven

Courtroom Spectator (uncredited)

John Tatham