A new start in Yonville coincides with the discovery that Emma is pregnant and the introduction of Léon Dupuis, a handsome and passionate law student who quickly becomes Emma's close companion and confidant.

Emma continues a double life of extreme contrasts: stolen time spent with her lover Rodolphe and writing to or dreaming about him, the counterpoint to domesticity. Charles' love for Emma renders him oblivious to her faults and his pride obliges him to indulge her naïveté in frivolities beyond their means. The Draper, Lheureux, supplier of these luxuries, increases profits by luring customers into his web of usury. As Emma's spending expands into expensive presents for her lover, Lheureux's debts mount.

Emma sinks deeper into the spiral of deceit and, in order to finance presents and trysts in Rouen, deeper into debt with Lheureux. When, on the death of his uncle, Charles is left property, Emma and Lheureux conspire to obtain power of attorney. Despite fierce opposition from her mother-in-law, she achieves this and continues to fund illicit meetings with Léon. Lheureux sells on the debt to another moneylender who gives Emm two days to find enough money to keep him at bay.