Alfred Hitchcock's <i>Blackmail</i> is a landmark in British cinema. Released in June 1929, it was hailed as "the first British all-talkie film." Characteristically, Hitchcock makes flamboyant use of the new technical and aesthetic opportunities that sound offered. But the film was also released in a silent version, and to this day some critics consider this version a superior work.<br> In his lucid and knowledgeable discussion, Tom Ryall covers both versions of the film. It is, he argues, both a considerable work of art in itself, and also one of the first to display those touches we now think of as typically Hitchcockian: a blonde heroine in jeopardy, a surprise killing, some brilliantly manipulated suspense, and a last-reel chase around a familiar public landmark (in this case the British Museum). There's also a cameo appearance by the director himself, as a harassed traveller on the London Underground.