A prodigy whose gifts terrified the people around him, John von Neumann transformed every field he touched, inventing game theory and the first programable computer, and pioneering AI, digital life, and cellular automata. Through a chorus of family members, friends, colleagues, and rivals, Labatut shows us the evolution of a mind unmatched and of a body of work that has unmoored the world in its wake. The Maniac places von Neumann at the center of a literary triptych that begins with Paul Ehrenfest, an Austrian physicist and friend of Einstein, who fell into despair when he saw science and technology become tyrannical forces; it ends a hundred years later, in the showdown between the South Korean Go Master Lee Sedol and the AI program AlphaGo, an encounter embodying the central question of von Neumann's most ambitious unfinished project: the creation of a self-reproducing machine, an intelligence able to evolve beyond human understanding or control.