Lady Ivy Wentworth cannot find her twin brother. At their last meeting, Ian was troubled by revelations from their mother regarding their parentage. Ivy, a seer, has dreams that her brother is in peril. When the Home Office, with whom she is secretly employed, asks her to investigate missing diamonds at Winter Garden estate, Ivy agrees, believing the answers she seeks are there. Upon arriving, Ivy finds Garrett Burke. Two years ago, Ivy thought she would marry Garrett, until he left her bed and did not return. Humiliated, Ivy turned her focus on her work.

Two years ago, Garrett Burke was betrayed and almost killed by a blow to his head. Garrett lost parts of his memory. He did not recover the Martello diamonds, nor does he remember who betrayed him. A lead on the diamonds sends him to Winter Garden to investigate. The estate was used in a smuggling operation and is filled with secret rooms and tunnels. Somewhere in the house are the answers he craves. If success means working with Ivy, so be it. He does not trust her, but he remembers parts of their love affair.

Ivy and Garrett form an uneasy alliance. She will work with the devil if it allows her to find her brother, whose life she feels is in peril. Inseparable, Ivy and Garrett look for answers. Their relationship builds with promise, but the past must be reckoned with before there can be a future.

Ms. Ashworth pens a memorable historical romance with a suspenseful mystery. The ingenious plot twist and mesmerizing characters make this an explosive and thrilling page-turner. A NOTORIOUS PROPOSITION should gain new fans for Ms. Ashworth.