Errol Morris's meditation on the myth of Sisyphus profiles four esoteric professionals -- a topiary gardener (George Mendonca), a lion tamer (Dave Hoover), a robot scientist (Rodney Brooks) and a mole-rat photographer (Ray Mendez). Though each is in a separate world, Morris asks us to contemplate what makes them four-of-a-kind, as his film explores the metaphysical meeting point between the animal, the mechanical and the human.