The Fleischer brothers, Max and Dave, were animation pioneers. Creators of Betty Boop, Koko the Clown, and the Bouncing Ball, they also brought Popeye the Sailor Man to the screen and produced the first feature-length animated cartoon—on the theory of relativity! Max invented the Rotoscope and for a while the brothers kept pace with Disney in performance and profit. But after 1942 the studio closed and their films vanished. What happened and how they developed are examined for the first time in this work—for many years out of print and a collector's item. It is here, updated and enlarged with hundreds of sketches and storyboard layouts where these classic cartoons can once again receive the attention and adulation they deserve.