Eccentric social outcast Lady Gwenevere St. James knows many secret things: magic, alchemy, artifice, and even the truth about the long-forgotten faeries. But she does not know why common criminals are using rare and dangerous magic to kidnap orphans from the streets of New London.

After rescuing one young girl, Gwen vows to save the rest, no matter the cost. But the handsome Scotland Yard inspector is also investigating the case, and he thinks Gwen knows far too much about the kidnappings to be innocent.

To save the children, Gwen must dodge the Inspector, bully a coven of witches, and outsmart her marriage-minded mama, all while managing a wily young pickpocket and a headstrong raven. But an unexpected secret hides at the center of the mystery, one that will force her to confront the most painful event from her past, and possibly sacrifice her future.