Louis Levy (20 November 1894 – 18 August 1957) was an English film music director and conductor, who worked in particular on Alfred Hitchcock and Will Hay films. He was born in London and died in Slough, Berkshire.
As a child Louis Levy played the violin, beginning with a toy violin that his father bought him at the age of seven. He later became the pupil of Guido Papini but due to his parents' limited means, ended his studies with Papini and began a period of self-study. This led to him gaining a scholarship at the London College of Music. Papini refused to allow Levy to study under anyone else, so resumed his tuition, this time free of charge. 
He started his career in 1910 arranging and performing music for silent films.  In 1916, he became musical director for the New Gallery Cinema in London. In 1921, he became Music Chief at the Shepherd’s Bush Pavilion and is credited with being the first to develop the theme song in movies, and one of the first musicians to tackle difficulties that were holding back the progress of sound recording in films.  
At the beginning of talkies, he joined the Gaumont British studios at Shepherd’s Bush, where he was musical director for Gaumont's earliest sound picture, High Treason (1929).  He became the head of the music department for all Gainsborough Pictures productions from 1933 onwards.  The rich sounds emanating from his large orchestra are all the more impressive when one realises that electrical sound industry was barely ten years old. He worked in particular on Alfred Hitchcock and Will Hay films, directing the music for The 39 Steps and The Lady Vanishes . 
Through the sheer necessity of having to produce so much music he established his own studios (The Levy Sound Studios at 73 New Bond Street) in the 1930s.  He later had a long running BBC radio series Music From the Movies, which started in 1936 and lasted until the 1950s,  and also toured the provincial theatres with his orchestra.  The Music From the Movies March, reputedly composed by Levy, was the theme tune for the radio show, and opened all of the Gaumont newsreels of the time.  He is also said to have composed the orchestral piece Maltese Entr’Acte. 
In 1948, Levy became general musical director for the Associated British Picture Corporation,  and during the 1950s he was head of music at Elstree Studios, where the films he worked on included Moby Dick (1956).  Unlike his counterparts at other studios, Muir Mathieson and Ernest Irving, who cultivated art composers to contribute film scores, Levy operated a department of specialised staff composers and arrangers, closer to the Hollywood system. Among the talented arrangers he employed were Peter Yorke (who adapted the Levy sound for his own successful post-war concert orchestra) and Bretton Byrd, who was his chief music editor at Gaumont British. 
Although often given the only musical credit on films for which he supervised the music, Alexander Gleason has argued that Levy did not compose or arrange the scores for any of the 250 talkies with which his name is associated. 
(Sole credit for the music, often as musical director, unless otherwise noted)
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