Lady Bronwyn Chase is far from the paragon of society that her mother expects her to be. That's how she finds herself on her brother's passenger liner bound for America carrying a secret packet of letters that could get her into trouble—the kind of trouble that a duke's sister shouldn't be in, the kind that puts spymaster Valentine Medford, the Duke of Thornbury, on her trail. Serious trouble. But as the duke gets closer to Bronwyn and the secrets she's keeping, he'll have to decide between the mysterious woman who calls to him or his allegiance to the Crown.