Eleventh century Cambridge is rocked by a series of brutal murders. Called out to attend a body found on a lonely stretch of river bank, its throat torn out, apprentice healer Lassair is sceptical of the sheriff’s verdict that this was the result of a wild animal attack. But when a second body is discovered, similarly mutilated, rumours engulf the town that the legendary demon known as the Night Wanderer has returned to wreak havoc.