Confessions of a Dangerous Duke (On His Majesty's Secret Service #3)
Patricia Barletta

Cameron, Duke of Lythmore, an agent for the English government, is an expert at sniffing out secrets and destroying spy rings. But this time, his mission in Bath is personal. He is determined to find the mysterious woman, nick-named Marguerite, who lured his brother to his tragic end. When Cameron meets Arianne, he is immediately drawn to the beautiful modiste. Surely, a woman who creates such charming designs could not be the cruel Circe. Or could she?
But there is one more secret that could destroy them forever.