The year is 1142, and England is in the grip of civil war. Within the cloisters of the Benedictine Abbey of Saint Peter and Saint Paul, there begins a chain of events no less momentous than the upheavals of the outside world.

It starts with the sad demise of Richard Ludel, Lord of Eyton, whose ten-year-old son and heir, also named Richard, is a pupil at the abbey. The boy refuses to surrender his newly inherited powers to Dionysia, his furious, formidable grandmother. A stranger to the region is the hermit Cuthred, who enjoys the protection of Lady Dionysia, and whose young companion, Hyacinth, befriends Richard. Despite his reputation for holiness, Cuthred's arrival heralds a series of mishaps for the monks. When a corpse is found in Eyton forest, Brother Cadfael must devote his knowledge of human nature to tracking down a ruthless murderer.