The early versions of both the screenplay and the soundtrack followed Kipling's work more closely, with a dramatic, dark, and sinister tone which Disney did not want in his family film, leading to writer Bill Peet and composer Terry Gilkyson being replaced. The casting employed famous actors and musicians Phil Harris, Sebastian Cabot, George Sanders and Louis Prima, as well as Disney regulars such as Sterling Holloway, J. Pat O'Malley and Verna Felton, and the director's son, Bruce Reitherman, as Mowgli.