Trivia

For the opening of this movie, Sir Alfred Hitchcock wanted to show the Avenger's murder victim being dragged out of the Thames River at night with the Charing Cross Bridge in the background, but Scotland Yard refused his request to film at the bridge. Hitchcock repeated his request several times, until Scotland Yard notified him that they would "look the other way" if he could do the filming in one night. Hitchcock quickly sent his cameras and actors out to Charing Cross Bridge to film the scene, but when the rushes came back from the developers, the scene at the bridge was nowhere to be found. Hitchcock and his assistants searched through the prints, but could not find it. Finally, Hitchcock discovered that his cameraman had forgotten to put the lens on the camera before filming the night scene.

For the opening scene, where the Avenger's murder victim faces the camera and screams, Sir Alfred Hitchcock filmed the scene by having the actress lie down on a large sheet of glass, with her golden hair spread out around her head. He then lit the actress from underneath the sheet of glass, and filmed her with a camera mounted on its side, with the lens pointed at a downward angle. This gave the appearance that her hair (with its golden curls, so important to the murderer) was ringed in a halo of light.

This is the first movie directed by Sir Alfred Hitchcock in which he makes one of his trademark cameo appearances. Here, it's as "Extra in Newspaper Office". A modern source also has him standing in a crowd as the leading man is arrested.

Sir Alfred Hitchcock's first commercial hit.

Sir Alfred Hitchcock told François Truffaut that, though he had made several movies prior to this, he considered this his first true suspense film.