Moore and Caine play dual roles—a pair of small-time con-men and a pair of inept nuclear physicists who believe they have invented a limitless supply of energy. The con men use their resemblance to the scientists to con their way into the scientists' safe deposit boxes and steal the formula, but in so doing, they become entangled in a shady world of spies and international intrigue. The film includes a number of cameo appearances, including Jenny Seagrove (Winner's partner at the time) playing two different roles, John Cleese, Patsy Kensit, Alexandra Pigg and Nicholas Courtney. The film also features Roger Moore's daughter, Deborah Moore, in a supporting role.