During an attempted rape, Alice White kills her assailant in self defense. Her fiancé, Frank, a London detective, is assigned to the case, and he soon begins to suspect that Alice is involved. After a witness comes forward and threatens blackmail, Alice must decide whether to tell Frank the truth about what happened that night. *"BLACKMAIL marked Hitchcock's first use of sound, and it remains famous for innovations in that area. But it's now more stimulating for its experiment with narrative structure." - Tony Rayns, **Time Out***