When John Posthumous Lerici, decadent poet, black magician and unacknowledged son of Lord Byron, is murdered, the family hire Inspector Swain.

His investigations lead Swain through the familiar hunting grounds of Victorian Brighton and Pimlico. But as the truth of Lerici's criminal associations come to light, it reveals the corruption of Scotland Yard officers by two of the century's most skilful international swindlers and blackmailers, Harry Benson and Billy Kurr.