Hildegard, no longer a member of the Cistercian order of nuns, has returned to the priory after more than a year from her pilgrimage to Santiago de Compostela, Spain. Still unsure whether she will rejoin the Order, the Prioress suggests that a visit to Handale Priory might help provide some clarity. Used as a house of correction for sinning nuns, it lies in the north of the county in the middle of a vast wood and is run by the ambiguous Abbess Basilda and her close group of hard-faced acolytes. While walking about the grounds, Hildegard discovers the corpse of a young man in the morgue. His body bears deep gashes from neck to groin. His wounds appear to be the ravages of claws, but larger than any animal Hildegard knows of. Is it possible that the young man was killed by a dragon, as Hildegard's been told? Of course, Hildegard does not believe in dragons, and despite being warned against it, she goes for a walk in the woods. There she discovers a secret tower, locked and barred, with armed men on guard. What is so valuable that it needs such protection? Has it anything to do with the mystery of the young man's death? And why have assassins been pursuing the King's courier across the savage moor land only to murder him at a lonely wayside tavern? Hildegard risks all dangers to seek out the truth.