Indiscreet by Candace Camp

Benedict Wincross appears in Camilla Ferrand's life as quickly as the gunfire pursuing him. Though his name belies the fact, he is obviously no gentleman. But Camilla realizes Benedict may be just what she needs: a temporary fiancé to satisfy her family's worries.

And Benedict needs something in return: an entrée into Chevington Park, Camilla's estate, to conduct an undercover investigation into corruption—without Camilla's knowledge. Each was drawing the other into a dangerous deceit—for even if they survived the danger of Benedict's mission, how would they undo the love between them?

"[Camp] is renowned as a storyteller who touches the hearts of her readers time and time again." --RT Book Reviews