Numerous attempts to adapt the "Doctor Dolittle" series began as early as the 1920s. In the early 1960s, actress-turned-producer Helen Winston acquired the film rights in an attempt to produce a film adaptation to no success. In 1963, producer Arthur P. Jacobs subsequently acquired the rights and recruited Alan Jay Lerner to compose the songs and Rex Harrison to star in the project. After numerous delays, Lerner was later fired and replaced by Leslie Bricusse. The film encountered a more notoriously protracted production with numerous setbacks along the way such as complications from poorly chosen shooting locations, creative demands from Harrison, and the numerous technical difficulties inherent with the large number of animals required for the story. The film exceeded its original budget of $6 million by three times.