The Jerk

Navin Johnson (Steve Martin) is the adopted son of a poor black sharecropper family, whose crazy inventions lead him from rags to riches... right back to rags. Navin goes through a string of misadventures, becoming smitten with a lady motorcycle racer, surviving a series of screwball attacks by a deranged killer, and becoming a millionaire by inventing the 'Opti-grab' handle for eyeglasses.