Based on a true story, Mickey Rooney portrays Bill, a 40-year-old mentally retarded man with an I.Q. of 50, unable to read or write, living in the brutal rough and tumble of New York City. He must learn the ways of the city or face going back to the institution in which he spent a better part of his life in. Barry Morrow (Dennisn Quaid), an amateur documentary filmmaker, befriends and enables Bill to learn about family and true friendship. Edie McClurg costars. The sequel, Bill on his Own, also starring Rooney, continues the tale of courage, strength, and understanding as the generous and sensitive Bill becomes independent and self-sufficient.