On a lonely moor in the northeast of England, the body of a young woman is discovered near the site of a vanished church. In the south, a girl lies buried beneath a Saxon mound. To the southeast, the ruins of a priory hide a human skull. Each is a sacrifice, a summons. And something in the shadows has heard the call. But another is coming: Parker the hunter, the avenger. From the forests of Maine to the deserts of the Mexican border, from the canals of Amsterdam to the streets of London, he will track those who would cast this world into darkness.