British gangster George Thomason (Tom Georgeson) and his hapless aide, Ken Pile (Michael Palin), draft a pair of arrogant Americans, grifter Wanda Gerschwitz (Jamie Lee Curtis) and weapons expert Otto West (Kevin Kline), for a massive diamond heist. When the job goes badly, Wanda attempts to seduce George’s stuffy lawyer, Archie Leach (John Cleese), to find out where George hid the diamonds. Meanwhile, Ken repeatedly attempts to kill an elderly woman (Patricia Hayes) who witnessed the robbery.