In the winter of 1940, ten-year-old Zachariah Yovanov's life is turned upside down in a single evening. While his father is away fighting on the frontlines of the World War II in Poland with the Soviet army, his mother is slaughtered by a demon in a munitions factory. When the same demon comes to seek him out, Zachariah flees the attacker, and on the snowy, lonely streets of Moscow, he finds the most unlikely of allies-a mysterious fallen angel named Red, who helps him to safety and then vanishes. After being taken into custody of an orphanage, Zachariah quickly realizes that his encounter with the supernatural was not just a one-night fluke. Demons and other fallen angels begin to appear to him everywhere, and he seems to be the only one that can see them. With the world at war matching the war waging within, Zachariah finds that he must come to terms with an identity he only barely understands and his place in a great cosmic struggle that goes back to beginning of time.