George Kemble, the man forever fixing everyone else’s problems, finds himself plagued by troubles of his own when his sister returns to London after a decade abroad. Sidonie Saint-Godard has lost her husband, but widowhood, unfortunately, bores her. When a thief called the Black Angel begins haunting the hells and alleys of London, robbing rich gentlemen of the ton, Kemble is mystified. He knows every member of London’s underworld, yet he does not know the Angel. But when a battered Sidonie collapses on his doorstep, bleeding from a nasty stab wound, Kemble begins to suspect the truth. Can he stop Sidonie’s dangerous behavior before someone else does?

Perhaps the Marquess of Devellyn can? The man unaffectionately known as the Devil of Duke Street has a watchful eye on his new neighbor, the mysterious Frenchwoman known as Madame Saint-Godard. In fact, he would like very much to seduce her, since he finds the lady lovely, intriguing, and almost disturbingly familiar . . . But when Kemble hears of his sister’s fascination with society’s most reviled nobleman, he is doubly alarmed. The Marquess of Devellyn is the absolute last person Kemble wants his sister in bed with—and for reasons which have nothing to do with Devellyn’s appalling reputation.