Short summary - Odile
The main character Roland Rami returns to civilian life after several months of service in Morocco, where he took part in hostilities. In Paris, through the mediation of one of his army comrades, Rami becomes a member of a small group of young people who meet in the Montmartre area, who practice the art of living without tiring themselves. Like the rest of the members of this group, Rami does not work eight hours a day at any enterprise and can manage his time on his own. For the next six months, not really striving for this, Rami rotates in this society of free swindlers.
Roland Rami is an amateur mathematician, so he spends several hours every day doing endless calculations that do not bring him a single sous. He also occasionally writes articles for scientific journals. Once upon a time he had a break with his family, and the only relative with whom Rami still has a relationship is his uncle. He served in the colony for a long time, has a fair amount of capital and monthly, in order to avoid the starvation of his nephew, lends him a certain amount of money.
After six months of his stay in Paris, Roland Rami becomes close to a group of communists who are trying with great diligence to convince him to join the party and actively support the cause of the revolution. The leader of the group is a certain Aglares; his life, according to the stories of the poet Saxel, an acquaintance of Rami, is permeated through and through with secrets and unusual incidents. Aglares wears long hair, a wide-brimmed hat, and a pince-nez that is attached to his right ear with a thick red cord. In general, he looks like an antediluvian photographer, and only the red tie around his neck indicates his modernist habits. Aglares gathered around him a number of students and, having enlisted their support, brings under the revolutionary struggle as a whole the idea of the prevalence of a certain "irrational", "unconscious" principle in the world, checking the correctness of the actions taken, including by himself, with the help of occultism.
Through the same group of "swindlers" Rami meets Odile, to whom he soon begins to experience a kind of friendly affection. Odile is in the group in the position of the girlfriend of Louis Tesson, a man with an uneven character, about whom everyone speaks with a kind of fearful admiration. This is a rough, bony type; once before, Odile even hated him.
At the request of Odile Rami writes an article on the objectivity of mathematics. The article turns out to be extremely favorably received among Aglares. Aglares is thrilled to finally meet the man who, in his opinion, discovered the infrapsychic nature of mathematics. From now on, he is even more actively trying to involve Rami in revolutionary activities.
After a while, Rami and Saxel visit the revolutionary occult sect of Mr. Muyard, where one of Rami's acquaintances, a certain F., invites them, and where F.'s sister, Eliza, a girl-medium, invokes the spirit of Lenin, who had already died by that time, allegedly through she gives posthumous instructions to all adherents of his revolutionary theory. Saxel is captivated by Eliza's charms and diligently tries to convince the Aglares group to join the Muyard sect. Saxel's enthusiasm, however, is not supported.
On the very evening that the question of joining the sect is discussed in detail at a meeting of the group, Oscar, the leader of the Montmartre company, kills Tesson, Odile's lover, who is his brother. The perpetrator of the crime is arrested on the same day, and together with him, several other acquaintances he and Roland have in common come to the police. Rami himself manages to avoid arrest only thanks to a timely warning from one young well-wisher. Over the next few days, Rami searches for Odile to no avail. His excitement is great, since she does not appear in her room. Two days after the crime, two police officers come to Rami's home and unceremoniously take with them all his papers, the bulk of which are mathematical calculations and extracts from highly scientific publications.
With the assistance of Aglares and one of their mutual acquaintances, Rami seeks to return all his notes to him, as well as to remove any suspicions from himself and Odile. Odile, deprived of her livelihood after Tesson's death and not confident enough to go to work, leaves for the village to stay with her parents. Rami, having lost her company, falls into depression, but soon finds a way to return Odile to Paris: he decides to bring her as his wife, inviting her to formalize a fictitious marriage. He really does not want to become her husband, because he is sure that he does not feel love. Roland convinces his uncle to double his pay in connection with his marriage, goes after Odile and, offering her his surname and modest income in exchange for simple friendly feelings, brings her back, thereby saving her from the village hibernation and hopelessness of existence. Having signed, young people continue to live separately and meet only a few times a week, and Rami, subconsciously not believing in his right to happiness, gradually removes Odile from himself further and further.
During Rami's absence in Paris, a coup takes place in Aglares's group: Saxel is expelled from it, and on the sheet defaming the poet, along with other signatures, there is the signature of Rami, who actually sees this paper for the first time. In addition, for the sake of expanding the influence of the group among the radical Parisians, unscrupulous people are admitted to its ranks, knowingly capable of meanness and betrayal. Such an unexpected turn of events contributes to the fact that for Roland Rami a certain period of political education ends, and he gradually moves further and further from the communists. Rally gets rid of the idea of himself as a mathematician, or rather, as a calculating machine, constantly losing count, and tries to "build" from the wreckage of his pride a new, more human refuge, in which there would be a place for such a feeling as love to a woman. Odile is the first to confess his love to Rami. Rami, hoping to think about his future life and figure out himself, for a few weeks with his friends goes to travel to Greece. There he finds the strength to abandon the constantly tempting desire to suffer and, looking into his soul, to understand that he loves Odile. Arriving in Paris, he still manages to regain Odile's disposition, no longer fearing to be just a "normal" person, and begins to treat this state as a springboard from which he can jump into the future.