Will is born into a world of magic and monsters carrying scraps of memory from a wasted life on Earth, and grows up in a ruined city of the dead. Three undead raise him there: Blood, a blunt skeleton warrior; Mary, a mummified priestess; and Gus, a cantankerous ghost sorcerer. They drill him in the sword, in magic and in faith, and when Will starts asking what keeps the three of them bound to the ruins, the answer pushes him out of the only home he has known.