From a New York Times–bestselling author: A former spy is recruited to unmask a vampire hunter in this Locus Award Winner. James Asher, a retired member of the Queen’s secret service in Edwardian England, has settled into quietude as an Oxford professor of philology with his physician wife, Lydia. But his peace is shattered when he’s confronted by a pale aristocratic Spaniard named Don Simon Ysidro, who makes an outlandish claim that someone is killing his fellow vampires of London, and he needs James’s help to ferret the culprit out. The request also comes with a threatening ultimatum: Should James fail, both he and his wife will die. With James’s talent for espionage and Lydia’s scientific acumen and keen analytical mind, the couple begins an investigation that takes them from the crypts of London to the underworld circles of the unliving to the grisly depths of a charnel house in Paris. Now James and Lydia must believe in the unbelievable—if they're to survive another night in the shadow of Don Simon Ysidro.
