Co-existing peacefully for five hundred years after creating their magically protected valley, the surviving members of four non-demon races band together against frightening creatures that are penetrating the shield around their home.

Eighty years into the future, the United States is a no-man's-land: its landscape blighted by chemical warfare, pollution, and plague; its government collapsed; its citizens adrift, desperate, fighting to stay alive. In fortified compounds, survivors hold the line against wandering predators, rogue militias, and hideous mutations spawned from the toxic environment, while against them all stands an enemy neither mortal nor merciful: demons and their...