After a cataclysmic fallout segmented the United States into safe zones and radiation zones, survivors in Texas are on their own. And survival depends on having clusters of radiation-curing nanites injected into the blood. When Chloe Santos's nanites fail, her parents, Nala and Manny, make a plan to find a colony that can help. Their best chance is Soteria, a hidden facility rumored to have the doctors and the tech capable of reprogramming nanites. But getting in comes with a disturbing price, forcing everyone involved to confront what it actually means to be human, who is worth saving, and what it means to be saved. 

Through the experiences of characters like Menori Yen, a cryonicist who can see ghosts, to Opal, a clone girl struggling with her humanity and identity, to Hugo Lafayette, a former wasteland criminal looking for redemption, and Dr. Rohan Singh, a crazed doctor willing to experiment on everyone and everything to revive the dead, the lines between life and death begin to blur.​