England, 1814. Lucien, Viscount Ware and Lady Anne are spending their honeymoon at his country estate in Lincolnshire. While attending an outdoor play at the May fête, a single cry is heard from the woods, thought to be the sound of a fox. The next morning the body of a young woman is discovered. The village immediately suspects the girl's beau, the arrogant son of the local magistrate. Constable Willis asks for Lucien's assistance, and Lady Anne urges him to agree after she meets the young man's distraught sister who believes in her brother's innocence.

Just as Lucien, Lady Anne and Constable Willis learn of a stolen diary and uncover age-old motives of jealousy and unrequited love, the inquiry is interrupted by the sudden appearance of armed strangers in the estate woods. One of them says he's a Bow Street Runner after an escaped mass murderer from London.

An intensive hunt for the fugitive, another murder, a terrorized village, danger to Ware Hall itself, and the arrival of Lucien's fellow intelligence agent with shocking news force Lucien and Lady Anne to put the honeymoon on hold while they hunt for not one but two killers.