London, 1817: Rosalind Thorne, daughter of a baronet, struggles to live on her own after her father and older sister fled to the continent to escape his debts, and her mother passed away. By her godmother's help, she escaped absolute destitution, and now serves as "a useful woman" to society women in need of someone to manage their parties and such. But when she goes to meet her godmother, a patroness of Almack's, the most exclusive public ballroom in all of London, her godmother is nowhere near the meeting room of the lady patronesses. What Rosalind does find is a body in the ballroom. With a believable heroine and well-rounded characters, as well as a twisting plot full of secrets and cover-ups, A Useful Woman should satisfy readers of cozy and historical mysteries.