When her convent is attacked by possessed soldiers, Artemisia defends the Gray Sisters by awakening the revenant bound to a saint's relic, even though she runs the risk of being possessed permanently by the powerful ancient spirit.

The dead of Loraille do not rest. If the bodies of the deceased are not cleansed so their souls can pass on, they will rise as spirits with a ravenous hunger for the living. When her convent is attacked by possessed soldiers, Artemisia defends it by awakening an ancient spirit bound to a saint's relic. It is a revenant, a malevolent being that threatens to possess her the moment she drops her guard. But Artemisia is desperate against the soldiers, and turns to the last remaining expert for help: the revenant itself. -- adapted from jacket