Five hundred years after Armageddon, Mankind has built a new civilization on the ruins of the old. Much technology has been lost, much has been rediscovered, and those who wield "lost" technologies have real power. Enclaves of survivors have evolved into new nations separated by vast distances. Massive airships provide transport between these distant outposts. At the center of this new world stands the Vatican, which emerged from the cataclysm as the guide and protector of humanity. But the Vatican is divided by special interests and secret societies, and the rise of Mankind is opposed by a new predator: Vampires. To fight this new threat, Caterina, Duchess of Milan and a Cardinal of the Church, heads a secret tactical team known as AX. Their chief agent, the priest Abel Nightroad, is secretly a Cruznik, a new species neither human nor vampire that feeds on vampires. Nightroad and his young prot￿, a human airship-pilot-in-training, are destined to play a pivotal role in Mankind's struggle against the Undead.