A musician walking home along the Rue Chaptal in the early hours of the morning sees a panic-stricken woman call for help from an upstairs window; moments later he hears a gun shot. He tries to go to her assistance, pushing past the man who opens the door upon his frantic knocking, but he finds himself roughly ejected from the premises. Undeterred, he heads for the nearest police station and urges Maigret to return with him and find out what has taken place.

With this look into the man he once was and how he became the insightful inspector we have some to know, Simenon offers new insights into the brilliance of Maigret.