When Peregrine Beaucliffe becomes the ninth Duke of Cullenmore he is determined to do his duty, which includes fulfilling a promise to his grandfather to marry before he reaches thirty. He does not see this as a problem, because it has always been accepted that he would marry the highly eligible Lady Honoria Flintley. All Perry has to do is propose. However, as the responsibilities of his new role press in upon him, Perry decides that he will take a holiday before he settles down to his new life, a holiday that includes a visit to one of his smaller properties, a sham castle prophetically named Duke's Folly…