The Grass Is Greener (UK-import)
When an aristocratic British couple (Cary Grant and Deborah Kerr) open their stately home to the public, a Texan oil millionaire (Robert Mitchum) enters their private quarters and successfully seduces the wife. The Earl then tries to win back his wife by enlisting the help of an ex-girlfriend (Jean Simmons), ultimately challenging his rival to a good old-fashioned duel.