"Blackmail" owes its place in film history to the fact that it was the first major British sound film. It exists in two quite separate versions, one sound, one silent, and is one of the first films to have the Hitchcock touch, as in the chase sequence around the British Museum. Tom Ryall examines the film's unusual production history, and places it in the context of Hitchcock's other British films of the period. This text is part of the "BFI Film Classics" series. Each volume in the series presents a personal commentary on the film, together with a brief production history and a detailed filmography, notes and bibliography.