Lucien is ruined, his lover Coralie is dead and his brother-in-law is imprisoned because of his debts. On the banks of the Charente, he is about to fire the gun which he points to his head. Father Herrera manages to dissuade him.
Locked up in an austere convent, Esther despairs over her separation from Lucien, while the latter has resumed his worldly life but has lost the taste for living.
While Clotilde's passion for Lucien flares, Vautrin's plot against Nucigen progresses. He makes Esther sign IOUs for 300,000 francs. Then, through the intermediary of one of his representatives, he haggles for the delivery of the young woman to Nucigen. The banker finally agrees to everything. Then Carlos Herrera summons Lucien and Esther. He tells them that their dream is finished. Taking Lucien away from him, he explains to Esther how she should behave with Nucingen.
Baron de Nucingen's passion for Esther is so intense that Herrera's crooked accomplices will make the banker pay dearly for the happiness of being able to love the young courtesan. Esther has sworn not to betray her love for Lucien.
The mysterious Monsieur de Saint-Estève announces to Lucien that the maneuvers against Baron de Nucingen will be revealed if he does not agree to pay him a large sum of money.
During Herrera's transfer to the Conciergerie, Asia, his accomplice, causes an incident and tells him that Lucien has been arrested. From the depths of his dungeon, the abbot hatches a plan to put pressure on Judge Camusot .
