The next morning, Wilhelm learns that Lothario has been wounded in a duel connected to a romantic dispute. A distressed young woman named Lydia reacts violently to the news. Lothario returns injured but alive, attended by Jarno. Wilhelm notices a surgical pouch that reminds him of the doctor who was told to treat him by the lady he knows only as the “Amazon.” The abbé explains the circumstances of the duel and invites Wilhelm to remain at the estate, where he’s now welcomed.

Lothario, recovering from his wound, reflects on his past neglect of practical duties and resolves to reform the management of his estate for the benefit of his dependents. He discusses his plans with Jarno, who advises delay due to financial concerns, but Lothario insists on acting immediately. After Lydia is removed from the room, Jarno reveals to Wilhelm that the count—the same count who was scared by Wilhelm’s appearance in his bedchamber—intends to join a religious community and that this situation involves Lothario’s sister. Wilhelm reacts with alarm but remains at the castle. He speaks with Jarno about his theatrical experiences, while Jarno dismisses his criticisms as universal human behavior.

Wilhelm summons the physician who gave the manuscript to Aurelia. After the physician tends to Lothario, he reports on the harper’s mental state; the harper believes that a boy will cause his death, which may be why he hurt Felix on the night of the fire. Jarno and the physician then decide that Lydia must be removed, as her emotional behavior hinders Lothario’s recovery. Wilhelm agrees to assist in deceiving her into leaving. During the journey, Lydia speaks of her past relationship with Lothario and her rivalry with a woman named Theresa. After traveling through the night, they arrive at a country house where a young woman (Theresa) appears, causing Lydia to faint.

Wilhelm is received at Theresa’s house. She explains Lydia’s anger and refusal to see Wilhelm: Lydia has forgiven Lothario while blaming Wilhelm. Wilhelm defends his deception, stating that he acted for Lothario’s health. Theresa expresses agreement in her high opinion of Lothario and acknowledges her own past attachment to him, though she maintains her composure. She hopes to form a friendly understanding with Wilhelm.

As they take a walk, she explains her independent management of her property and assists a neighboring steward. Wilhelm observes her knowledge and decisiveness in agricultural matters. She rejects the idea of marriage for wealth, emphasizing self-sufficiency. Upon returning to the house, Wilhelm examines the orderly house and garden, noting the careful arrangement of all objects. Reflecting on the “gifted” Theresa’s abilities and her connection to Lothario, he considers the influence that Lothario has on those around him and anticipates that the noblewoman he seeks may ultimately be connected to Lothario as well.

Theresa describes her childhood in a household divided between an orderly, capable father and a “quick and changeful” mother (406). She inherited her father’s practical nature and became skilled in managing household and estate affairs, while her mother despised her and engaged in wasteful, scandalous conduct. After her father’s death, Theresa was left dependent on her mother but later proved her abilities while overseeing another lady’s property. There, she met Lothario, who admired her practical intelligence and eventually asked for her hand. Theresa accepted, hoping for a life of useful work and mutual respect. However, their engagement collapsed when Lothario recognized a portrait of Theresa’s mother as that of a woman with whom he had previously had an affair. He left abruptly and never returned. Theresa rebuilt her life through disciplined work and modest independence, while Lydia became his companion.

As Wilhelm prepares to return to Lothario’s castle, the recovering Lydia warns him of Lothario’s “false and artful friends” (419), urging Wilhelm to look into the mysterious tower at the center of the castle to which Wilhelm isn’t permitted entry.

Lothario resumes riding. One evening, he recounts how weakness and returning strength made the countryside appear unusually vivid, reminding him of a “little love concern” from his youth (421). He rides again to the farm where he once loved a farmer’s daughter named Margaret and first mistakes her cousin for Margaret herself. The resemblance revives his earlier feelings, and he later returns to see Margaret directly. He finds her altered by marriage and motherhood yet still dignified and natural. The sight moves him deeply and leads him to reflect that, though renewed love can be sweet, a lasting union with Theresa would have given him the steadier happiness of a useful life.

Wilhelm speaks of Aurelia and asks why Lothario ignores the boy believed to be his son. Lothario denies any knowledge of such a child, and Jarno explains that Aurelia merely took the boy in. Jarno also notes that Wilhelm has “no talent” for the stage. Disturbed, Wilhelm resolves to fetch Felix and Mignon. Before he departs, Lothario relates his second visit to Margaret, which leaves him thoughtful and subdued.

Wilhelm returns to town thinking of Mariana, the “noble Amazon,” and the unhappiness of women. At the theater, he finds Mignon and Felix with Aurelia’s old maid, who is revealed to be Barbara, Mariana’s servant. She reveals that Mariana is dead and gives him her last letter, which says that Felix is Wilhelm’s son and that Mariana died faithful to Wilhelm. Wilhelm is shaken but still doubtful. Barbara later produces letters that confirm that Mariana resisted Norberg, loved Wilhelm sincerely, and tried desperately to reach him after their separation. Wilhelm is overcome by grief. He arranges for Barbara to take both Felix and Mignon to Theresa since Mignon refuses to be separated from the boy. He then withdraws from the theater, parts kindly with Madame Melina, and writes to Werner that he has abandoned the stage and now seeks a more grounded life.

Wilhelm returns to Lothario’s castle and finds Lothario gone to claim his late uncle’s inheritance. Jarno and the abbé involve Wilhelm in inspecting lands that Lothario hopes to buy. Wilhelm notices that they still conceal much from him, especially the mysterious tower. At dawn, however, Jarno leads Wilhelm into a hidden chapel-like chamber, where several figures appear one after another and speak cryptic judgments about his life, errors, and education. At last, the abbé gives him an “indenture” stating general truths about art, action, judgment, and true mastery. Wilhelm sees rolls labeled with the apprenticeships of Lothario, Jarno, and himself and realizes that his life has been watched and recorded by this strange society. When he asks the question nearest his heart, the abbé confirms that Felix truly is Wilhelm’s son. Felix is then brought in, and Wilhelm embraces him with overwhelming joy as the abbé declares his apprenticeship “done.”