Floating eyes from Venus invade Earth.; Following an atomic war, the human survivors live underground, building machines to do their work for them. Years later, they return to the surface, leaving the machines behind, but the machines begin to think for themselves, and rise up to conquer the surface world.; A professor postulates a giant being roaming through space that could eat the planets of the solar system, but that could also be eaten by an even larger being.; A creature from an underground civilization is sent as a scout to determine the weaknesses of the surface world, but none of the surface dwellers are afraid of his monstrous form, as he expected.