The music that plays whilst Basil Rathbone develops his wife's photo in the cellar is from Edvard Grieg's "Peer Gynt Suite" - In the Hall of the Mountain King.
This is Joan Hickson's first role in an adaptation of a story by Agatha Christie. 47 years later, she was cast as Miss Jane Marple in C'è un cadavere in biblioteca (1984), playing the character a total of 12 times from 1984 to 1992. In 1946, she had acted in a stage production of "Appointment with Death". Christie was so impressed by her performance that she wrote to tell her "I hope one day you will play my dear Miss Marple."
This movie was banned from public showing in Sweden by the Swedish Censorship Board in June 1937. Censorship number 55.945.
The failure of the original copyright holder to renew the film's copyright resulted in it falling into public domain, meaning that virtually anyone could duplicate and sell a VHS/DVD copy of the film. Therefore, many of the versions of this film available on the market are either severely (and usually badly) edited and/or of extremely poor quality, having been duped from second- or third-generation (or more) copies of the film.
This film received its earliest documented telecast Saturday 12 August 1944 on New York City's pioneer television station WNBT (Channel 1).