The novel takes the reader to Paris in early August. It is a rather hot and stale summer in the city, where breezes are few, and those that arise tend to be arid and dry. Enough to make anyone wish for rain.
At the headquarters of the Police Judiciaire at Quai des Orfèvres, Inspector Maigret feels very much like a man under siege. The press, sensing that a big story is about to break, have made themselves like permanent fixtures in the police station. Over the past 6 months, there have been a number of murders of young women in the Montmartre section of the city. Maigret has been hard pressed to determine who the murderer could be, as well as a possible rationale behind the killings. Most of the novel is taken up with the steps taken by Maigret to set up a trap to snare, once and for all, the murderer and restore tranquility in the neighborhood.