Thirteen generations ago, the ambitious first Duke of Magnussen made a fell pact with an unknown power, who asked for but one thing in return: the thirteenth daughter born to a Magnussen Duke.Now, generations hence, the daughter of Duke Magnussen XIII is stolen away by a hooded executioner riding a leathery beast. As it wings back across the city walls to drop behind the Duke’s mountain top keep, all who watch know it alights in the Magnussen family crypts, where the devilish secrets of thirteen generations have been buried and forgotten – until now…