A zany sense of humor fused by a psychedelicized vision made Robert Crumb one of the most influential comic artists of the 1960s. His characters, including Fritz the Cat, Mr. Natural, Flakey Froont, and the Vulture Demoness, and his underground comic books, such as Zap Comix, combined elements of social commentary and the British tradition of caricature. His illustrations often graced the covers of record albums, including one for Big Brother & the Holding Company's Cheap Thrills. Comics, however, represented only one side of Crumb's eccentric persona. A clawhammer-style banjo...