On his way home from a conference, Maigret stops to visit an old school friend in Fontenay-le-Comte. A man in the same train car introduces himself and asks if Maigret has come to help solve the murder case. In fact, the man’s brother-in-law had been murdered four days earlier, followed by the murder of a local widow in the same way, a blow to the head with a pipe. While Maigret is in town, a third murder is reported. Maigret soon discovers that there are two warring factions in the town, a clear class separation, and an air of suspicion that only he can put to rest.