Every full moon, a Ripper runs amok on the streets of Brentford. Masters Simon and Keith Innes set out to catch the killer under the disturbing guidance of the repellently delightful sleuth, Mrs. Bradley. Full of the very British eccentric goings-on that mark the popular tales of Gladys Mitchell, this shows her at her mordant and morbid best.

Psychoanalyst Mrs Bradley advises her highly-strung friend, Hannibal Jones, to retreat to a quiet, rustic village to find rest and inspiration for his writing. Saxon Wall seems the perfect rural retreat, and Jones is quickly intrigued by the odd characters among the villagers, their pagan beliefs, and by the mystery surrounding Neot House.

Alastair Bing's guests gather around his dining table at Chaynings, a charming country manor. But one seat, belonging to the legendary explorer Everard Mountjoy, remains empty. When the other guests search the house, a body is discovered in a bath, drowned. The body is that of a woman, but could the corpse in fact be Mountjoy? A peculiar and sinister sequence of events has only just begun.

It soon transpires that most of the village seem to have been wandering about Manor Woods, home of the mysterious druidic stone on which Sethleigh's blood is found splashed, on the night he was murdered, but can she eliminate the red herrings and catch the real killer?