An elderly man floats in a spaceship throughout the galaxy, with only a robot for a companion. The ship is arranged just like his favorite room on Earth, even down to the smallest dust particle, according to the robot. But the man is anxious to leave the ship for a bigger life. Together, they travel throughout the galaxy searching for a new habitable planet, since Earth has become uninhabitable. The robot, however, is sworn to keep humans from coming to harm. Every alternative planet discovered is not good enough for the man to live, according to the robot. But the man is tired of being stuck on the ship, no matter how comfortable it is. Desperate to leave, he rebels against his robot -- only to discover just how seriously the machine takes its charge to protect the man, even from himself.