A motley crew of four robbers pull off a diamond heist in downtown London, but they must then must deal with how to get the diamonds safely out of the country. The sexy, but calculating Wanda Gershwitz (Jamie Lee Curtis) and the brawn-over-brains Otto (Kevin Kline) turn in Wanda's lover, Georges Thomason (Tom Georgeson) in an attempt to keep the diamonds for themselves. Wanda and Otto keep animal-lover Ken Pile (Michael Palin) around to get rid of the elderly witness Mrs. Coady (Patricia Hayes), but Ken finds himself distraught when his attempts to silence the witness silence her pet dogs, instead. Wanda and Otto also discover another problem: Georges moved the diamonds before his arrest and he's not divulging their new hiding place until they manage to extract him from his legal trouble. Wanda looks outside the box for a different solution, namely seducing Georges' barrister, Archie Leach (John Cleese) to learn the whereabouts of the diamonds. A farce of stratospheric proportions ensues as all four of the robbers attempt to outwit each other, all while trying to keep the truth from Archie, whose good sense is obscured by his interest in the beautiful Wanda.