Who is the darkly handsome Don John 'Black Jack' Blackthorn? With his air of mystery and menace, the whispers about him hint of highwayman or government agent or even dark prince. But no one knows what it is Black Jack does...or how dangerous he can truly be. Now Jack's mentor has disappeared, and Jack must track him down before it's too late. His unlikely help: the man's daughter - the very woman Jack had once wooed and betrayed.

Lady Tess Fonteneau knows more about the fine art of clandestine activities - and about the mysterious Mr Blackthorn - than he realises. As their journey leads them on the adventure of a lifetime, their reunion is fraught with passion, high-stakes danger and the one twist of fate Jack never saw coming...