Endowed with inexhaustible wealth, unscrupulous Wall Street brothers Mortimer and Randolph think they know all about human nature. Eager to prove their radical theories, the stuck-up tycoons wager a bet on whether proper surroundings or strong genes define a person's life. With this in mind, they heap a mountain of misfortune on blissfully unsuspecting stockbroker Louis Winthorpe III, forcing him to trade places with Billy Ray Valentine, a streetwise nobody with no future. But as the cold manipulators pit heredity against environment for their perverse pleasure, pressing questions arise. Can Valentine become Winthorpe overnight? Will disgraced Louis turn to crime like a duck takes to water?—Nick Riganas