Alfred Hitchcock wrote in 1982: "The Hitchcock touch had four hands, and two were Alma's." Hitchcock began work on his tenth film, "Blackmail" (1929), when its production company, British International Pictures (BIP), converted its Elstree studios to sound. The film was the first British ""; it followed the first American sound feature film, "The Jazz Singer" (1927). "Blackmail" began the Hitchcock tradition of using famous landmarks as a backdrop for suspense sequences, with the climax taking place on the dome of the British Museum. It also features one of his longest cameo appearances, which shows him being bothered by a small boy
Stereophonic sound year later, MGM started using three tracks instead of one to record the musical selections of movie soundtracks, and very quickly upgraded to four. One track was used for dialogue, two for music, and one for sound effects. The purpose for this form of multitrack recording was to make mixing down to a single optical track easier and was not intended to be a recording for stereophonic purposes. The very first two-track recording MGM made (although released in mono) was "It Never Rains But What It Pours" by Judy Garland, recorded on June 21, 1938, for the movie "Love Finds