A young police constable arrives from the West of England. He has seen his sergeant, a man of the greatest rectitude, ignore a confession of a murder by a vagrant when a young girl was killed on their patch and the murderer never found. Holmes and Watson travel west to the small village of Weston Stacey where, disguised as a man of leisure interested in folklore, Holmes begins his investigation into the mysterious death of Bea Collins.
Amid the bustle of harvest time Holmes gathers together the unanswered questions: How did the killer know Bea would take a shortcut home rather than her usual route? What strangely shaped instrument was used to deliver the blow to her head? Why were traces of sugar cubes found at the scene of the crime? And what of little Billy Hayter’s insistence that he has seen a monster decorated with human skulls?
To Watson’s dismay Holmes is convinced that they have stumbled across some terrible evil and, as the last sheaves come in from the fields, the great detective exposes a unique and grotesque horror.