When Russian composer Sergei Prokofiev visited Hollywood in the late 1930s, his friend and American champion, maestro Leopold Stokowski, was recording The Sorcerer’s Apprentice, to be used in Fantasia. Prokofiev was indelibly impressed by Walt Disney’s work. He saw how the Disney artists made their animation efforts adhere closely to pre-recorded music tracks; he experienced the click track, a device developed by Disney to ensure that sight and sound were closely coordinated. He then returned to Russia to work with Sergei Eisenstein on the epic film Alexander Nevsky.