Dr. Hawley Harvey Crippen
Belle Crippen
Ethel Le Neve
R.D. Muir (as Sir Donald Wolfit)
Captain McKenzie
Mr. Tobin
Dr. Pepper
Mrs. Clara Arditti
Mrs. Jackson
Bruce Martin
Chief Inspector Dew
Lord Chief Justice
Harry
The Governor
Dr. Rogers
Mr. Arditti
Miss Curnow
Harding
Chemist
Police Sergeant Outside Courtroom (uncredited)
Defence QC Clerk (uncredited)
Radio Officer Andrews (uncredited)
Ships Steward (uncredited)
Courtroom Spectator (uncredited)