At sixteen, Sarah Tolerance scandalized Society when she ran away with her brother's fencing master. After his death, Society expected her to follow the route of all Fallen Women, and become a courtesan.

But Sarah Tolerance has never done what was expected of her. Instead, she reinvents herself as an Agent of Inquiry - a private investigator for the Quality. Able to slide between social layers, Miss Tolerance unearths secrets, finds things that were lost, and loses things too dangerous to be kept....

Tasked to find an antique fan the Earl of Vermillion's father once gave to "a lady with brown eyes," the job seems a simple enough. But Sarah soon discovers that she is not the only ones seeking the fan - and that it holds greater secrets than anyone knew. Secrets that may put England, and Miss Tolerance, at risk.

Worse, she finds herself drawn to the Earl, an attachment that they both know is impossible - and may put her in even greater danger...