The Saviors appeared in the sky on Judgment Day and created the Kingdom of Heaven on Earth – by force. Under the Saviors’ forbidding guidance, no one starves and no one dies of disease and angels keep the peace. But when 16-year old Yasmeen Robertson fishes a drowning boy out of the Chicago River, peace is the last thing she finds. Yaz and the boy have stumbled upon a yatsa drev, a piece of Savior-tech that makes them the subject of unwanted – and deadly - attention. Demons, whose hatred of the Saviors knows no bounds, are determined to have it for themselves. The Saviors, who have dispatched an archangel for the purpose, are determined to have it back. Neither are known for their mercy or understanding. If Yaz and the boy surrender to the archangel, they run the risk of being executed. If they throw their lot in with demons, there’s a good chance of being murdered. On the run, they struggle to unravel the yatsa drev’s mysteries. But Yaz has another problem: whether to trust the boy, whose uncle is the archangel pursuing them.