The case, which turned out to be extremely painful for Commissioner Maigret, began with an anonymous letter: an unknown person announced that a murder would soon occur. Megrae immediately notices expensive velvet paper in an unusual format. Due to this circumstance, it is possible to quickly find out that the letter was sent from the house of the lawyer Emil Parandon, a specialist in the law of the sea. Having made the necessary inquiries, the commissioner finds out that Parandon made a very profitable party: he is married to one of the daughters of Gassin de Beaulieu, chairman of the court of cassation.
Maigret calls Parandon asking for a meeting. The lawyer receives the commissioner with open arms: it turns out that he had long dreamed of discussing with the professional the sixty-fourth article of the criminal code, which defines the criminal sanity. Maigret carefully studies the owner of the house: he is a miniature and very mobile person with glasses with thick glasses - in a huge, luxuriously furnished study he looks almost a dwarf. Parandon instantly recognizes his paper and reads a strange message, without showing surprise, but jumps up from the place when an elegant woman of about forty with a tenacious look enters the office absolutely silently. Madame Parandon is burned with a desire to find out the reason for the visit, but the men pretend not to notice it. After her departure, the lawyer, without any coercion, talks about the inhabitants of the house and their lifestyle. The couple has two children: eighteen-year-old Poletta is engaged in archeology, and fifteen-year-old Jacques studies at the Lyceum. The girl came up with her brother's nickname Bambi and Gus. The secretary Mademoiselle Bar, the intern Rene Tortue and the young Swiss Julien Bod, who dreams of becoming a playwright, and for the time being doing small assignments, work with a lawyer. Maid Lisa and the butler Ferdinand live in the house, the cook and the cleaning lady leave in the evening. Parandon gives Megre complete freedom - all employees will be ordered to openly answer any questions of the commissioner,
Megre tries not to spread too much about this case. He is a little ashamed of the fact that he is engaged in nothing. There is no reason to suspect that drama is brewing in the house of Parandon - everything seems to be orderly, measured, orderly. Nevertheless, the commissioner is again sent to a lawyer. Mademoiselle Wag answers his questions with restrained dignity. She frankly admits that they have moments of intimacy with the cartridge, but always in fits and starts, because there are too many people in the house. Madame Parandon, perhaps, knows about this connection - once she went into her husband’s office at a very inopportune moment. The secretary’s room is a real entrance house, and Madame is simply omnipresent. You never know when she will appear - by her order the floors are everywhere covered with carpets.
A second anonymous letter arrives at the police: an unknown person warns that as a result of the Commissioner's embarrassing actions, a crime could be committed from hour to hour. Megre meets again with the secretary - he likes this smart, calm girl. She is clearly in love with her patron and believes that it is him who is in danger. The house is run by Madame Parandon. She has a bad relationship with her daughter - Bambi considers her father a victim of her mother. Perhaps there is some truth in this: the Gassenov family has prevailed over the Parandons - neither relatives nor friends of the lawyer are actually here. Gus loves his father, but hesitates to show his feelings. Maigret is becoming increasingly worried. He already knows that about 6 spouses have weapons. Madame Parandon, with whom he had not yet spoken, called the police herself. She is impatient to enlighten the commissioner regarding her husband: the unfortunate Emil was born prematurely — he never managed to become a full-fledged person. For twenty years now she has been trying to protect him, but he goes deeper into himself and completely fenced off from the world. Matrimonial relations had to be terminated a year ago - after she found her husband with this girl secretary. And his manic interest in one of the articles of the criminal code - is this not a psychosis? She was scared to live in this house.
Megre meets lawyers and servants. Julien Baud claims that everyone knows about the connection between the cartridge and Mademoiselle Wag. This is a very nice girl. The future playwright believes that he was lucky: the married couple of Parandonov are ready-made characters in the play. They meet in the corridor, like passers-by on the street, and sit at the table like strangers in a restaurant. Rene Tortu behaves very restrained and only notices that in the place of the cartridge he would lead a more active life. Butler Ferdinand frankly calls Madame Parandon a bitch and a damn cunning woman. The spiritual master was unlucky with her, and talking about his insanity is complete nonsense.
Maigret receives a third message: the anonymous author claims that the commissioner actually provoked the killer. Constant monitoring is established in the house: at night Inspector Lalwent is on duty, in the morning he is replaced by Janvier. When the bell rings, Megre's heart involuntarily tightens. Janvier reports the murder. With the spouses Parandon, everything is in order - Mademoiselle Wag was stabbed to death.
Together with the investigative team, Megre hurries to a familiar house. Julien Baud cries, not ashamed of tears, the self-confident Rene Tortue is clearly depressed, Madame Parandon, according to the maid, has not yet left the bedroom. It was established that the girl had her throat cut at about half-past nine. She knew the killer well, as she continued to work calmly and allowed her to take a sharp knife from her own table. The commissar goes to the lawyer - he sits in complete prostration. But when Madame Parandon appears with a plea to confess to the murder, the little lawyer begins to stomp in fury - to the full satisfaction of his wife.
After her departure, Gus bursts into the office with a clear intention to protect his father from Megre. The commissar already guessed who the author of the mysterious anonymous letters was - it was a purely boyish undertaking. After talking with Bambi, Megreet's other assumption is also confirmed; children are burdened by the lifestyle that their mother imposes on them. But Bambi, unlike his brother, considers Parandon a rag and does not like Mademoiselle Bar.
The commissioner leaves the interrogation of Madame Parandon in the end. She repeats that she took sleeping pills at night and woke up at about twelve. The murder, of course, was committed by her husband - probably this girl blackmailed him. However, he could have done it without reason, because he is obsessed with the fear of illness and death - it is not for nothing that he refuses to deal with people of his circle.
Meanwhile, Inspector Luke interrogates the residents of the house opposite. Among them there is a disabled person who stays by the window all day. From his apartment you can clearly see the lounge of the Parandonov. Madame came out at about half-past nine - a maid busy with cleaning should have seen her. Locked to the wall, Lisa no longer unlocks and apologizes to the hostess.
In the dresser, Megre finds a small browning. When Madame Parandon came out, the revolver was lying in her pocket in her bathrobe. Most likely, at that moment she was going to shoot her husband, but then another thought occurred to her. Killing the secretary, she could not only strike him, but also bring all suspicions to him. The revolver was not needed, because on the table at Antoinette there was a sharp knife for cleaning up typos.
Having decided to deliver the suspect to Orfevre embankment, Megre again goes to the lawyer - Parandon has an occasion to study article sixty-fourth in more detail. In the car, the commissioner recalls the wording, terrifying in its vagueness: “There is no crime if, during the commission of the act, the accused was in a state of insanity or was forced into the force that he could not resist.”
