Dr Courtine, an unworldly academic is visiting an old friend in the Cathedral town of Thurchester in the late 1870s. On his first night he is told the story of the town ghost, a legend deeply mired in the medieval intrigues of the Cathedral when two prominent churchmen met their deaths in unexplained circumstances. The story of dark deeds in the ancient close captures Courtine's donnish imagination, and he is also embarking on some amateur sleuthing of his own - attempting to track down an elusive 11th century manuscript to prove his theories about the life of King Alfred. Suitably distracted, Courtine becomes the unwitting witness to a terrible crime committed on his own doorstep ...