Juliet Boucheron struggles to maintain and keep her ancestral home despite the threat of high taxes and a rash of unexplained break-ins. As a widow, she works hard to protect her son and younger sisters. Juliet hides the reality of their situation from her family until a telegram arrives warning her of impending danger. Terrified of trusting anyone, Juliet once again starts searching her home for the gold her late husband was accused of stealing before the war ended.

Stephen Trevelyan arrives at the Boucheron mansion hiding his own secrets. Unable to contend with his involvement with his sister-in-law's death, Stephen needs a place to write. Appearing at the Boucheron mansion, he obtains a room as a boarder. Intermingling with the other boarders, Stephen perceives the darkness and turmoil that permeates the inhabitants. His growing attraction to Juliet distracts him from his real purpose in being there.

Juliet tentatively accepts Stephen's aid, but cannot give him her full trust. There are still too many unanswered questions surrounding him. The consequences of her trusting the wrong person would harm not only her, but also her family. The suspense mounts until a murder occurs and Juliet has no choices left.

Teeming with menacing atmosphere, this sequel to MISTRESS OF TREVELYAN continues along the Gothic path. St. Giles captures that Gothic essence with a sinister plot, complete with unusual twist and turns, while maintaining a strong sexual tension between the protagonists.