When nightclub owner Émile Boulay disappears without a trace, initial evidence suggests an act of revenge in the red-light district. Just a few weeks earlier, the leader of a Corsican gang was shot dead in broad daylight. However, Inspector Maigret is reluctant to believe that the hardworking, modest Boulay had crossed paths with gangsters. Two days later, Boulay is found strangled at the Père Lachaise cemetery. It takes quite a while before Maigret stumbles upon a clue. When he finally uncovers it, he is completely astonished and then allows his emotions to run free.