Psychic Lassair finds the body of a young woman, and becomes involved in the search for the killer. Suspicion points to the brother of the woman who is about to become Lassair's sister-in-law!

In Autumn of 1093, Lassair encounters a veiled noblewoman on the quay at Cambridge, set on by an angry mob. She has no idea that the woman, alone but for her infant child, brings both mystery and peril. Then a devastating flood hits the fens, and among the wreckage washed up at Aelf Fen is a body. Lassair, in the company of a sheriff's officer, wonders if she is dealing with murder. Meanwhile, in the south, Lassair's beloved Rollo is moving with relief...

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 sheriffs 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.