This documentary highlights the cinematic accomplishments of Ub Iwerks, a forgotten genius overshadowed by the towering presence of Walt Disney. The details include his early life in Missouri, his teaming up with Disney, and the creation of his most famous work: Mickey Mouse. The film provides an in-depth look into the world of American animation during the '20s and '30s, including some rarely seen animated gems. After Iwerks left Disney to set up his own company, he became one of the key innovators of animation and helped train a future generation of cartoon masters, including Chuck Jones.