It's 1920s London and young Alice White (Anny Ondry) is a shopkeepers daughter who is reluctantly dating police detective Frank Webber (John Longden). After staging a quarrel one night about their evening plans Alice is able to meet with a young artist (Cyril Ritchard) instead. While out walking with him he offers to show her his artists studio. She accepts. But when he tries to rape her she grabs for a knife and stabs him in self defense. She flees from the crime scene and Frank, of course, is the detective sent to investigate the murder. He finds her glove and immediately pockets it to protect her. But then a man comes forward (Donald Calthrop) claiming to have seen Alice with the artist that night. What will it take to keep this blackmailer quiet?
Blackmail was the first British film to feature sound and it was Alfred Hitchcock's first sound picture as well. It actually began production as a silent film (there are no voices for the first eight minutes of the film), but when Hitchcock learned that sound was available to him he was able to reshoot a few key scenes and make this his first talking picture. The only hurdle he had to get over was that his lead actress, Anny Ondry, had a thick Czech accent and post-dubbing was not yet available. He had to have actress Joan Barry standing offscreen with a microphone to dub Ondry's lines.
In silent pictures, according to Hitchcock, the villain was usually a man with a mustache. Hitchcock called the above scene, showing a shadow that looked like a huge mustache on the artists face before he attacks Alice, his goodbye to silent pictures.
Hitchcock's cameo in Blackmail is at the ten minutes mark. The lead characters are on the underground and he is shown trying to read a book while be bothered by a young boy.
