Split-identity story of a gentle middle-aged cartoonist, creator of intrepid Diamond Sutro, unaccountably locked in the same body as an American Nazi leader. There's a third self unknown to the others, and a still more buried remnant awaiting its own moment. The action spins between a posh Earthside funny farm, a robot supercivilization to which the multiple selves are summoned to save the universe, and the Diamond Sutro cartoon plot's increasing encroachments on outside realities--with additional disturbing (and not awfully well-managed) WW II flashbacks. The denouement is brought off with confidence though in several shades of purple. A superior and stimulating effort.