Humanity fled a dying Earth centuries ago, scattering across eighty colonies connected by the Astra Gates — a network that has long since gone dark. On the mining world of Sacramentum, the colony of Erigo sits on the one substance that could bring the Gates back to life: deorum, a living metal the Praetorium will do anything to control.

Poppy Hadley is an engineer racing to hold a reactor together on the day of the most ambitious deorum experiment ever attempted. She knows the safety margins are gone. She knows nobody is listening. And when the city comes down around her, she's left digging through the rubble for the only family she has — and finding a message that was never meant for her. A message someone built to survive exactly this.

Mason Wright is a security officer and the Governor's son, a man who chose the uniform over the family name. In the hours before the catastrophe, evidence lands in his hands suggesting the disaster may not be an accident at all. Evidence that people will kill to bury — and that his own father may not want found.

To get answers, Poppy and Mason must survive a ruined city, a security commander with his own agenda, and forces that were hunting through the wreckage before the dust had even settled. Because whatever destroyed Erigo isn't finished. And what it woke up may matter more than what it killed.