This series has run to several books, varying in quality -- Sister Frevisse, a well-born nun and niece to Geoffrey Chaucer, is the investigator. Previous books have dealt with life inside the cloister, court life (Frevisse's cousin is married to nobility) and the intrigues between the princes of the church and English nobility in the 14th century.
The present book, however, deals with village life and government and simple human greed. Master Naylor, the priory's steward, is part of the village court of Prior Byfield, as is Simon Perryn, reeve. After some decisions in favor of the village's richest man, Gilbey Dunn, rumor and murder appear to threaten the positions of Naylor, Perryn and Dunn -- Naylor is accused of being a runaway villein and Perryn and Dunn are incriminated in the death of Perryn's sister's lover.
After Naylor is accused of not being freeborn, Sister Frevisse is instructed by her prioress to take Naylor's position in the court. Despite the non-cooperation of the crowner, several misdirections and a measles outbreak, Frevisse not only involves herself in the life of the village and its government, but also determines the identity of the miscreant or miscreants and helps bring them to justice.
I found the final scene of the book quite special; I could envision the end of harvest and what it meant to the villagers.