Professor Stepan Stepanovich Lozhkin, all his life safely engaged in literary monuments of heresies and sects of the XV – XVI centuries, suddenly began to attend a “dangerous thought”. Its existence: lecturing, work on manuscripts, relations with his wife - it seems to him monotonous and "machine". Malvina Eduardovna, frightened by the manifestations of her husband’s “second youth” in order to slightly change her lifestyle, invites guests. The assembled representatives of the "old", academic science condemn obscure and insecure "formalists". We are also talking about Drahomanov: it is not customary to talk about him here, but that is precisely why his strange behavior, dark past and addiction to drugs are of universal interest.

Thirty-three-year-old Boris Pavlovich Drahomanov lives in a university dormitory, where everyone does not like him and is afraid of him. Drahomanov teaches several students the course "Introduction to Linguistics." At one of the lectures, he unexpectedly “renounces” the traditional theory of common Indo-European parent language and argues that development, on the contrary, comes from “the initial set of languages ​​to a single language.”

In one of the largest Leningrad publishing houses, there is a "mysterious and estranged from the real world" manuscript keeper. This little old man with a red beard was nicknamed Chaldean Haldeevich. Khaldey Khaldeevich does not like writers, restless and unreliable. He also really doesn’t like the “climb” Kiryushka Kekcheev, who suddenly turned from a courier into a boss.

A student of the Institute of Oriental Languages ​​Nogin, after talking with Dragomanov, comes to his ruined, neglected apartment. Nogin works hard and is intensively studying Arabic.

"Netsrylov, writer, brawler, philologist" returns to Leningrad from Moscow. Nekrylov is angry with his "friends" -literators, "sitting up and getting rich." He is preparing an offensive. Indeed, he succeeds in both successfully conducting business conversations in the publishing house, and on the go insulting the successful writer Robert Tyufin. In the evening, Nekrylov, accompanied by the beautiful Verochka Barabanova, visits Dragomanova. Then they all go to the Capella for a literary evening. There Nekrylov is noisily greeted, surrounded by flattery, asked to speak. Vera Alexandrovna runs away, offended by Nekrylov, because he promised to be at her evening.

Nogin arrives in Lesnaya, where the “economists”, his friends and fellow countrymen live the commune. Nogin in despair: he is in love with Verochka Barabanova. Returning home, Nogin washed down. The student is touchingly looked after by his neighbor Khaldey Khaldeevich, and it turns out that he is the brother of Professor Lozhkin, but has been quarreling with him for many years. Meanwhile, Professor Lozhkin is "rebelling." He shaves off his beard and then hurries off while his wife is sleeping.

Nekrylov somehow senselessly "cheats" on his friend with his wife. On the occasion of the arrival of Nekrylov, a meeting of friends is arranged. Nekrylov continues to "scandal". Nobody understands him, the thought of the “pressure of time” remains without a response. Nekrylov is about to leave. When he comes to say goodbye to Verochka, it turns out that she is getting married to Kirill Kekcheev. Nekrylov is trying to dissuade Verochka, he is ready to "take her away from under the crown."

Nogrylov was greatly impressed by Nekrylov, whom he met with Drahomanov. Nekrylov talks about the choice of Vera Alexandrovna Barabanova and threatens to kill Kekcheev. After this news with Nogin, "something is amiss." He nevertheless goes to Verochka to warn of danger, but he catches it with that same “friend”. Then Nogin writes Kekcheev a letter.

Nekrylov came to the publishing house to “arrange” Dragomanov’s book and deal with Kekcheev, but he suddenly learns that Kekcheev is going to return his own manuscript to him. Nekrylov is making a real scandal ... A crowd of employees of one of the largest Leningrad publishing houses is helplessly watching how Nekrylov is rampaging, how he beats Kekcheev, how he ruins his office. Kekcheev, from fear, completely loses his human appearance and cowardly refuses the bride. Khaldey Khaldeevich this encounter is a real pleasure.

"Escaping" from his wife, Lozhkin went to his old gymnasium friend Dr. Neigauz. In a small remote town, he enjoys freedom. So the “rebellion” of the professor “left” in an ordinary “picnic”, in a noisy drinking party. Lozhkin returns to Leningrad. There, he accidentally meets Dragomanov, who apologizes for not very courteous behavior during their last conversation. But their current conversation ends with the offended Lozhkin running away in a fury. Professor wanders around Vasilyevsky Island. The wet and unfortunate Lozhkina is recovered from the next Vasileostrovsky flood by Khaldey Khaldeevich. They finally met, twenty-six years later. Khaldey Khaldeevich at first reproaches Stepan, who had fallen, because he once took the bride away from him, but then both cry, hugging. Nogin, who woke up after an illness, hears their conversation.

Repentant Lozhkin hurries home, but no longer finds Malvina Eduardovna alive, longing and ill without her husband. Lozhkin returns to his manuscripts in the Public Library. There was no “second youth”. Now you need to endure old age with dignity.

In the large hall of the institute are waiting for Drahomanov. Instead, a student Lehman appears, who reads a professor’s report "On the rationalization of speech space." The report proposes “to divide human speech into groups according to professional and social characteristics” and “draw strict boundaries between groups, the violation of which should be assessed with a corresponding fine”. Only after listening to the mocking conclusion - a request to return the missing Adler typewriter - did the audience finally understand what was happening. Scandal.

Verochka Barabanova does not know who to choose: she has already given the floor to Kekcheev, with him she will be able to calmly do painting. But Verochka Nekrylova loves, although he is married. Verochka is trying to solve this issue with the help of fortunetelling. Unfortunately, the choice falls on Kekcheev. But suddenly Nekrylov appears.

Nogin is gradually recovering. Everything that was before the disease now does not occupy him. One night, he, under the influence of Lobachevsky's theory, writes a story, in the ending of which two parallel storylines are connected. He understood what he was going for, what he was striving for. This is prose.

Railway station. Here Drahomanov escorts Nekrylova and Verochka to Moscow. Friends, as always, argue, almost quarrel. Already on the road, Nekrylov, under the impression of Dragomanov’s words, started a “vague conversation with his honesty,” reflecting on his mistakes and time. That night, Nekrylov falls asleep, Lozhkin sleeps, the whole Vasilievsky Island sleeps. And only Drahomanov does not sleep, he teaches Russian to the Chinese.