Rosalind Thorne may not have a grand fortune of her own, but she possesses virtues almost as prized by the haut ton discretion, and a web of connections that enable her to discover just about anything about anyone. Known as a "most useful woman," Rosalind helps society ladies in need--for a modest fee, of course--and her client roster is steadily increasing. Mrs. Gerald Douglas, n e Bethany Hodgeson, presents Rosalind with a particularly delicate predicament. A valuable pearl necklace has gone missing, and Bethany's husband believes the thief is Nora, Bethany's disgraced sister. Nora made a scandalous elopement at age sixteen and returned three years later, telling the family that her husband was dead. But as Rosalind begins her investigations, under cover of helping the daughters of the house prepare for their first London season, she realizes that the family harbors even more secrets than scandals. The intrigue swirling around the Douglases includes fraud, forgery, blackmail, and soon, murder. And it will fall to Rosalind, aided by charming Bow Street officer Adam Harkness, to untangle the shocking truth and discover who is a thief--and who is a killer.