When a laser-armed Department of Defense robot named Number 5 gets zapped by a lightning bolt, he "malfunctions" and starts spouting peace slogans and developing a human-like consciousness. Naturally, the newly pacifist machine wants out of the military and escapes. As a frantic search for the creature begins, Number 5 settles down in his new home, with a gentle young woman named Stephanie (Ally Sheedy), who has every intention of holding on to her find, teaching Number 5 about popular culture and other mysteries of life. Thoroughly convinced that the robot is alive, she develops a strong bond with the creature. In order to prevent his capture by the military--who view Number 5 as an armed-and-dangerous weapon--the pair must convince his inventor, a reclusive scientist named Newton Crosby (Steve Guttenberg), that he is truly alive and more than just a metal machine. The highly innovative robot created for director John Badham's film brings to mind other lovable science fiction icons such as E.T. and R2D2 from STAR WARS.