The body of a young student, Alys Thomas, is found in the centre of a vast expanse ofmarshlands by two young boys. She is dressed immaculately in a scarlet dress and seems to have been deliberately placed there.
Mathias, struggling with his own demons from the past, becomes more emotionally connected to the case than is wise, a fact not missed by Mared and Chief Super Prosser. With professional and personal loyalties pushed to the limit, Mathias finds himself on an emotional knife-edge.