In this sweeping Dust Bowl-inspired fantasy, a ten-year game between Life and Death pits the walled Oklahoma city of Elysium-including a girl gang of witches and a demon who longs for humanity-against the supernatural in order to judge mankind.

When Sal is named Successor to Mother Morevna, a powerful witch and leader of Elysium, she jumps at the chance to prove herself to the town. Ever since she was a kid, Sal has been plagued by false visions of rain, and though people think she's a liar, she knows she's a leader. Even the arrival of enigmatic outsider Asa-a human-obsessed demon in disguise-doesn't shake her confidence in her ability. Until a terrible mistake results in both Sal and Asa's exile into the Desert of Dust and Steel.

Face-to-face with a brutal, unforgiving landscape, Sal and Asa join a gang of girls headed by another Elysium exile-and young witch herself-Olivia Rosales. In order to atone for their mistake, they create a cavalry of magic powered, scrap metal horses to save Elysium from the coming apocalypse. But Sal, Asa, and Olivia must do more than simply tip the scales in Elysium's favor-only by reinventing the rules can they beat the Life and Death at their own game.