1740. With the whole of Europe balanced on the brink of war, an Austrian regiment is sent to the furthest frontier of the empire to hold the border against the might of Prussia. Their garrison, the ancient house called Pokoj.

But Pokoj is already inhabited, by a company of ghosts from every age of the house's history. Only Drozde, the quartermaster's mistress, can see them, and terrifyingly they welcome her as a friend. As these ageless phantoms tell their stories Drozde gets chilling glimpses not just of Pokoj's past but of a looming menace in its future.

Meanwhile the humourless lieutenant Klaes pursues another mystery. Why are the people of the neighbouring village so surly and withdrawn, so reluctant to welcome the soldiers who are there to protect them? What are they hiding? And what happened to the local militia unit that was stationed at Pokoj before the regiment arrived?

The camp follower and the officer make their separate journies to the same appalling discovery - an impending catastrophe that will sweep away villagers and soldiers alike. But to stop it would pit Klaes against his entire regiment and Drozde against the one man in the world she truly fears.

Perhaps neither of them can prevail. If they do, it will be with the help of the restless dead. . . .