After ten years, James is fed up with his boring marriage, but his wife, Caroline, still loves him. As he walks out on her, she warns: ""I'll never divorce you."" James's lawyer advises him that the best way to avoid years of delay is to catch Caroline being unfaithful. So James hires a private eye to follow her for a whole day, up to midnight, with little hope that it will do him any good - and he gets a surprise.