William Dunbar, the younger son of a Scottish nobleman, craves wealth, and marriage seems to be his simplest way to achieve it.

His pursuit eventually leads him to Mercy Grundy, an old maid in the eyes of mid-1740s society who fears lifelong spinsterhood. Her father has offered a substantial dowry to the man who will take her hand in marriage.

For William, marriage to Mercy would be a match made in heaven. But for Mercy, who has succumbed to William’s charms, would marrying him necessitate her taking one false step?