9th CHRONICLE: One of the rarer Cadfael novels. At the beginning of the twelfth century the civil war caused by the dispute between King Stephen and the Empress Maud continued to rage. When an exchange of prisoners was arranged it promised to be straightforward, hedged round by traditional safeguards. But before the exchange could be completed one of the valuable prisoners was murdered. Brother Cadfael it was whose observations proved that the man's death was not natural. And Cadfael gathered clues - very slender evidence but enough to bring a conviction of guilt if the pieces could be made to fit.