Peter pays a visit to Xenia, who, taking advantage of her charm, lures Peter to bed. Dressed in a man's dress, Varya decides to talk to the emperor. Paul listens favorably to her, but he does not intend to change his order against the cavalrymen. Grand Duke Constantine is subdued by Vari's extravagant act and asks her to stay at court. Tolstoy and Lugin await punishment. In the fortress, they unexpectedly meet Stepan, who tells them his story.

Peter in the house of Xenia learns about the impending coup. He hurries to warn the emperor, but his attempt fails - Kutaisov does not understand the importance of the letter and decides to give it to Paul in the morning. D'Arnie watches Peter and tries to kill him. Palen manipulates Alexander by showing him a warrant for his arrest. Alexander agrees to participate in the conspiracy. Mongo receives a signal that a coup has begun.

The beginning of great changes in the political life of Europe, the time of great generals. In the political arena, the influence of France, England and Russia is increasing. Napoleon Bonaparte is preparing for great deeds, but family battles prevent him from devoting himself to state affairs. Despite the requests of Napoleon, the Bonapartes do not intend to accept Josephine and her children. Napoleon, not wanting to participate in family dramas, goes to inspect the army.

Varya fails to prevent the duel between Peter and Tolstoy. But the end of the duel is unexpected - Cherkasov and Tolstoy become friends. Evdokia marries Olga for Mongo-Stolypin. Olga, offended by Peter, agrees to the marriage. Peter does not intend to retreat, seeing Olga's hesitation, he offers her a secret wedding. Pavel warns Alexander about the danger of friendship with the Polish prince. Elizaveta tells her husband about Czartoryski's letters. She assures Alexander that she does not find the Polish prince attractive.

Evdokia learns that Olga and Peter are going to get married in secret, and dissuades Olga. Olga informs Tolstoy and Peter that she refuses to run. Varya's mother, Aglaya, plays the cards of Varya's music teacher, the serf singer Stepan. Kuragin does not hide his feelings for Evdokia, but she is not ready to give an answer. The only thing she asks is to take Peter to Petersburg. Paul is sure that the Grand Duchess Elizabeth dishonored the royal family with her connection with Czartoryski. These thoughts offend Alexander.

Olga stops the fight between Peter and Mongo-Stolypin. Given a choice, she gives her life to Mongo. Evdokia, seeing the suffering of her son, regrets that she interfered with his happiness. Mongo-Stolypin claims to have saved Peter from the disappointments of family life. Stepan confesses his love to Varya - he ran away from the new owner only to see her. Varya thinks how to save Stepan. Czartoryski confesses to Alexander that he is in love with Elizabeth. Elizabeth hides Czartoryski's letter from Alexander.

Peter becomes close to the Grand Duke Alexander. Lugin becomes Konstantin's adjutant. Olga begins to get to know the life of the capital, Mongo pleases her with unexpected gifts. Arriving in Cherkasovo to visit Varya and Evdokia, Olga assures them that she is happy, but before leaving, she steals a medallion with a portrait of Peter. Polish conspirators, friends of Czartoryski's youth, ask Adam to assist them in kidnapping Alexander. Czartoryski does not want to participate in this.

Peter, accompanying the Grand Dukes on a walk, suddenly notices that mysterious strangers are shadowing them. Having begun their pursuit, he soon loses sight of them - in one of the alleys, strangers disappear without a trace. Konstantin persuades Alexander to continue the night walk, he liked the owner of the German tavern - Lenchen. Only in the morning the princes return to the palace. Polish conspirators - Tadeusz and Zosia are plotting the kidnapping of Grand Duke Alexander.

Peter and Lugin are conducting their own investigation. They explore the lane and find a secret underground hole leading to an inn. Having found out from the owner who else knows about the existence of the tunnel, they lie in wait for Zosya, but she manages to escape. Varya discovers that the medallion is missing, and informs Peter about it. Peter decides to have a frank conversation with Olga - he cannot forget her. Mongo-Stolypin, knowing what kind of medallion Olga wears on her chest, suffers but does not reveal the secret.

Mongo-Stolypin finds Peter coming to Olga. Olga is afraid of a scandal, but Mongo hides his jealousy and kindly invites Peter to the ball with them. At the ball, Peter confesses his love to Olga, but she, disappointed by the latest events, refuses him. Olga runs away from the ball, and Peter meets Palen's daughter, the adventuress, Xenia. Tadeusz and Zosya try to hurt Czartoryski's national feelings and force him to agree to participate in their plans.

Peter, the cavalry guards, and the Grand Dukes are trapped in a German tavern. Czartoryski tries to warn Alexander but does not have time, a fight breaks out. Konstantin, shortly before this, goes down to the backroom to Lenchen, trying to achieve reciprocity. But meets only surprise. The Grand Duke has a fit of anger, having come to his senses, he discovers the lifeless body of Lenchen nearby. Protecting Konstantin Lugin accidentally kills her husband Lenchen.

Czartoryski saves Alexander's life. Tadeusz is killed. Zoya manages to escape. When the police appear, Peter takes away the Grand Dukes, Tolstoy and Lugin remain with the wounded Okhotnikov. Thanks to Peter, the princes manage to evade persecution. When Peter returns to the tavern, his friends are no longer there - they were taken to the police station. Palen reports to Pavel about the night incident in the city.

The surviving Polish conspirators seek to hide, Zosia threatens the cavalry guards and Czartoryski to avenge their murdered brother. To avoid publicity, Peter takes the Grand Dukes away. Lugin and Tolstoy remain with the wounded Okhotnikov. Mongo-Stolypin is cold with Olga. To avoid suffering, he offers her free family relationships - such as many St. Petersburg couples have. Olga is offended and upset. Palen reports to Pavel about the events of the night.

Peter asks Alexander for his comrades in trouble. Alexander promises to help, but does not believe in a successful outcome of the case - Pavel is adamant. Olga decides to break off relations with Peter, she writes him a letter and gives it to the batsman. The cavalry guards are transferred to the Peter and Paul Fortress, where they must await punishment. Arriving in Cherkasovo, Aglaya complains of her loneliness, she wants to take Varya to St. Petersburg. Pahlen and D'Arny discuss the possibility of plotting against Paul and drawing Alexander to him.

Peter, having received the letter, penetrates the house of Mongo-Stolypin for a decisive conversation with Olga. Olga chases him away. Suddenly, Peter learns about the conspiracy against Paul, he cannot help but warn Olga that her husband is involved in this. Mongo, having been a bystander to the transfer of the letter to Peter, recognizes a familiar envelope. He further strengthens his suspicions of his wife's infidelity and decides to join the Masonic order.