Inspector Maigret is sent to the Mediterranean island of Porquerolles after a man named Marcellin is murdered in a small seaside inn. What makes the case unusual is that Marcellin had recently boasted to others that Maigret was his friend—a claim that puzzles the inspector, who barely remembers the man.

Shortly before his execution, a condemned man named Lenoir makes a final, cryptic confession to Inspector Maigret. He insists he is innocent of the crime for which he’s been sentenced—but not of all crimes. He once witnessed a murder, he says, at a riverside bar on the Seine, known as La Guinguette à Deux Sous ("The Two-Penny Bar").

Inspector Maigret takes a risky and unconventional step: he arranges the secret escape of Joseph Heurtin, a mentally challenged man convicted of a brutal double murder—an American woman and her maid in a Paris apartment. Though the evidence seems damning, Maigret is convinced Heurtin is innocent or, at the very least, not the mastermind.

On Christmas morning, Maigret and his wife are enjoying a rare peaceful holiday at home in Paris when they are visited by two women from their apartment building. One is Madame Martin, a young widow, and the other is her neighbor, Madame Doncoeur, a retired schoolteacher.

Madame Martin’s daughter, Catherine, has told an odd story: during the night, she awoke and saw Father Christmas in her room. But instead of bringing gifts, he appeared to be searching for something. The women are disturbed—not by the fantasy—but because they suspect someone actually entered the apartment.

Inspector Jules Maigret is unexpectedly sent to the small Dutch university town of Delfzijl to investigate a murder involving a French professor, Jean Duclos, who had been visiting the local college. A well-known womanizer, Popinga, is found dead, and suspicions fall on Duclos, who may have been having an affair with Popinga’s wife—or possibly with another woman in the town.

Inspector Maigret as he investigates the mysterious death of Colonel David Ward, an English multimillionaire found drowned in his bathtub at the luxurious Hôtel George-V in Paris. The case takes Maigret into the world of high society, where wealth and secrecy complicate the investigation.

After decades of cat-and-mouse, Maigret is keeping a quiet eye on Manuel Palmari, a once-powerful underworld figure now crippled and confined to his Paris apartment following a gangland shooting. Palmari is suspected of running a string of jewel thefts, but Maigret has never been able to pin anything on him.

On doctor’s orders, Maigret is taking a rest cure in the elegant spa town of Vichy, known for its mineral waters and serene routine. He spends his days walking, sitting on benches, and taking the waters — reluctantly relaxing.

While there, he notices a quiet, graceful woman named Hélène Lange who follows the same daily schedule as him. They exchange nods, but never speak.

Then — she is found dead, strangled in her hotel room.

Maigret receives a strange anonymous letter, written on expensive stationery and elegantly worded. The writer claims that a murder is about to be committed — but gives no names, only that it involves someone influential, and that Maigret must act quickly.

Maigret is called to the Norman coastal town of Bayeux, where Valentine Besson, a sharp and imperious elderly woman, has requested his help after the sudden death of her maid, Rose.