Family comedy following a robot who goes AWOL. A reclusive inventor, Newton Crosby (Steve Guttenberg), is responsible for the development of a range of robots that have the capacity to destroy entire cities. At a military demonstration, one of the robots is struck by lighting and is given a life of its own. The authorities decide that this is dangerous and want the robot terminated. Number Five (voice of Tim Blaney) duly goes into hiding with a fanatical animal lover, Stephanie Speck (Ally Sheedy), who believes he is an alien. Will she be able to protect him?