Miss Catherine Trevor is quite happy with her life at her father's estate of Rosemont and does not regret choosing to remain unmarried at the advanced age of nine and twenty. But a visit from her brother, his peevish wife and ill-mannered children causes Catherine to reconsider her status when she realizes she will eventually be dependent upon her brother if she does not establish her own household. Hearing that Lord Edgecombe, an unmarried marquess, will spend the coming autumn at a neighbor's estate, Catherine determines to bring the peer to an offer. Despite the disapproval of her family, who had hoped she would accept the hand of her long-time friend and neighbor, Lord Woodforde, Catherine goes forward with her plans to capture Lord Edgecombe's interest. With the aid of a friend she discovers what appeals to Lord Edgecombe and presents herself to please. The peer's interest is piqued and Catherine is soon betrothed - but no sooner has she achieved her goal than she begins to wonder if she has made a disastrous mistake. Bound by her word to honor the betrothal, Catherine must use her wits to find a way out of her predicament before her wedding day.