The Rising of the Moon

From: http://www.gladysmitchell.com/rising.htm
The narrator of this tale is Master Simon Innes, who spends a memorable spring investigating events occurring in his sleepy countryside village, with his brother Keith at his side. Village life, like its nearby river, is quiet and lazy, but the Innes brothers keep busy: they routinely inspect the contents of an eccentric lady's antique/junk shop; they do their best to avoid the unfriendly rag-and-bone man; and on occasion, when pressed into service by their sister-in-law, they take their toddler nephew out for a stroll. The arrival of a travelling circus on Easter weekend promises excitement, and it brings just that, but in an unexpected form: the body of a woman tight-rope walker is found on the circus grounds. She appears to have been mutilated the previous night, when the moon shone full.

The police arrest a circus performer who had a relationship with the victim, but he is released when a second woman--a barmaid at the local public house, the Pigeons--is murdered. The Innes brothers do some snooping about, and discover that both women were robbed after they were set upon. A third body is found, and Simon and Keith are dismayed and alarmed when they realize that their adult brother Jack, who acts as guardian to the boys, is mysteriously absent from the house on that last moonlit night. Furthermore, Jack's snob's knife is missing from his tool box, and he has begun acting in a strange manner.

To clear their brother's name, Keith and Simon continue to investigate, and in so doing, make the acquaintance of a peculiar elderly lady named Mrs. Bradley. From that point on, the Innes boys take Mrs. Bradley into their confidence (and, eventually, the old detective shares secrets with the boys), and the village prepares itself for the onset of another full moon. Is a Jack-the-Ripper lunatic at work, or do the murders have a more monetary motive? The answer may lie somewhere in the shadows between.