Hyde transition scenes in this film were  accomplished by manipulating a series of filters in front of the  camera lens, filters which alternately revealed and obscured  portions of Fredric March (qv)s Hyde makeup. During the first  transformation scene, the accompanying noises on the soundtrack  included portions of Bach, a gong being played backwards, painting  on the track, and, reportedly, a recording of director  Rouben Mamoulian (qv)s own heart.