A 14th-century Crusader returns to a homeland devastated by the Black Plague. A beleaguered church, deeming sorcery the culprit of the plague, commands the two knights to transport an accused witch to a remote abbey, where monks will perform a ritual in hopes of ending the pestilence. A priest, a grieving knight, a disgraced itinerant and a headstrong youth who can only dream of becoming a knight join a mission troubled by mythically hostile wilderness and fierce contention over the fate of the girl. When the embattled party arrives at the abbey, a horrific discovery jeopardises the knight's pledge to ensure the girl fair treatment, and pits them against an inexplicably powerful and destructive force.