Harriet and John Carker are deeply troubled and shamed by what their brother has done. One morning, Mr. Perch comes to see them, delivering a message from Mr. Dombey. After he leaves, they read the letter. As he expected, John Carker has been fired from his job. While he understands why Dombey would take this action, he is still distressed about what the future will hold. Harriet, to comfort him, reveals that they do have a friend: the mysterious stranger who visited, would not reveal his name, but promised to be of assistance should they need it. He has been passing by the house weekly since then, but since Carker’s disappearance with Edith, the visits have stopped. Harriet is sure he will return, and suggests that, when he does, he and John can meet and discuss a plan for the future.
Later that evening, someone comes to their door. John opens it and recognizes Mr. Morfin, whom Harriet identifies as the stranger who has visited her. Mr. Morfin has been working alongside Carker for years, quietly observing, but minding his own business. Because of the position of his office, separated from Carker’s only by a thin wall, he has been able to overhear many of Carker’s interactions, including the argument between John and James about the damage inflicted on the Carker reputation by John’s past behavior. Intrigued by this conversation, as well as the mention of a sister, Morfin had come to see Harriet. Without revealing his identity, he had made his offer to be of assistance if necessary, and has been visiting regularly ever since. Morfin did not want to get involved in case there was any chance of the siblings reconciling, but now he will be able to help them. He rises to leave, but then asks John to leave him alone with Harriet. When they are alone, Morfin guesses that Harriet has been wondering if Carker stole money and she confirms that she is anxious about this. Morfin explains that Carker has not directly stolen from his employer; he has, however, mismanaged the firm, taking extravagant risks. Harriet asks whether the business is in danger as a result, and Morfin explains that it needn’t be, if it is scaled back appropriately. If, however, Dombey refuses to recognize the altered circumstances, serious consequences could result. Morfin then leaves. The next night, Harriet is alone in the house when Alice abruptly appears. Alice wants to tell her story: she explains that when she was young, her mother realized how beautiful she was and desired to make a profit as a result. They were not of a social class where an advantageous marriage was a possibility; instead, Alice became the mistress of James Carker. When he discarded her, she was worse off than before and reduced to poverty, theft and prostitution. She was put on trial for theft and her mother went to Carker asking for financial help, which he refused. Her hatred for him was what led to her rejecting the money Harriet had first given her when she realized the connection between the two. Alice now confesses that she provided information about Carker’s whereabouts to Dombey, as part of her revenge. Since then, she has been tormented, horrified by what will happen if Dombey catches up to Carker. She tells Harriet that Carker is in Dijon, and begs her to find a way to warn him that Dombey is coming for him. Then Alice flees the house.
Edith is waiting at a hotel in France. After two attendants serve supper to her, Carker arrives for their planned rendezvous. He is surprised that she has not followed his instructions to hire a new maid, but is pleased that they are alone. He plans for them to continue on to Sicily. When he approaches her, Edith seizes a knife and threatens him. She makes it clear that she has arranged for them to meet alone but that she is planning to leave and has no intentions of the two being lovers, or continuing on together. She has always hated him, and staged the elopement only for the purpose of hurting and shaming both Dombey and Carker, as well as escaping from her marriage. Carker is furious but he is also frightened of Edith, and doesn’t know what to do. She also reveals that Dombey has located them, and will be coming in pursuit of revenge. Sure enough, a commotion begins in the inn, distracting Carker enough that Edith is able to slip away through a hidden passage she had prepared in advance. Carker is now distressed, overwhelmed, and afraid, and escapes from the hotel room through the same passage.
Once outside, Carker decides that the best thing to do is head back to England. He hires a coach and driver, and flees. As they drive, he becomes more and more paranoid about being pursued. He manages to flee back to England in a paranoid haze. As he waits on a train platform, anxious to get even further away, he recognizes Dombey coming towards him. Panicked, he falls onto the tracks and is struck by a train and killed.
Meanwhile, back at Sol’s shop, Susan has been located and returns with Toots and Chicken to take care of Florence. Toots declares that he is happy that Walter and Florence will marry, and vows his friendship. It is planned that once Florence and Walter marry, they will depart for China, since that is where Walter sailed after being rescued from his wrecked voyage, and where his fortune is now tied. Susan is determined to accompany her, but Florence persuades her that Walter will take good care of her. Time passes with preparations for the marriage, and the evening before the wedding, Sol Gills suddenly reappears. He is delighted to see everyone reunited, happy, and safe, but he asks Cuttle why Cuttle hasn’t answered the various letters he sent him. Cuttle is stunned and confused. Sol explains that he spent time in various parts of the West Indies looking for news of Walter and finally heard the story of him having been picked up by the China bound ship and now being on his way home. Upon hearing this, he also set sail to return to England. Cuttle swears he never received the letters, and it comes to light that Sol had, reasonably, addressed the letters to Cuttle’s former residence at the lodgings of Mrs. MacStinger. However, because he has so carefully hidden his whereabouts, there was no way for Mrs. MacStinger to forward these letters to him. On their way home, the Chicken suggests that Toots continue to fight for Florence’s hand and heart, which horrifies Toots. He is resigned to her marriage, and values his friendship with her. He and the Chicken part ways.
The next morning, Walter and Florence go and visit the grave of little Paul. Then, the two are married surrounded by their friends, and shortly thereafter board Walter’s ship and set sail. Walter leaves a letter to be delivered to Mr. Dombey, conveying the news of their marriage.
As the novel approaches its conclusion, closure starts to emerge in some of the plotlines. Florence and Walter are finally married, and the wedding, especially now that Sol how returned, signals that Florence has finally found the security and love she has always craved. The marriage, however, rather than providing a domestic retreat from the world as might be expected, will radically broaden her horizons in that she will sail with Walter to China. A wife accompanying her husband to sea was not typical at this time, and shows that Florence gives Walter the complete love and devotion she has always longed to offer to her father. It also reveals a new boldness to her: having taken the radical step of leaving her father's house, she can now survey her future fearlessly, and if she has love at long last, she does not have anything to be anxious about.
Carker's plot is also resolved with a punishment for his many evil deeds: a train, which is personified as a kind of demon, kills him. While it is possible that Dombey might have been intending to kill him, as was Alice's fear, this accidental death prevents that fate. It evokes instead a kind of poetic justice where Carker's paranoia emerges because he has made it impossible for him to trust anyone. He becomes obsessed with the idea of being watched just as he himself has been ever watchful in his spying and plotting. In effect, he is his own downfall.
There are also surprises that emerge even at this late juncture. Alice, despite her deep hatred of Carker, panics at the thought that she may have enabled his murder and attempts to save him. This shows that even her cynicism and bitterness have not completely hardened her, and that it is always possible for a character to have a change of heart and try to show forgiveness and compassion.
Edith is also revealed as having different intentions than might be expected. She is not actually involved in an adulterous affair, and reveals that she has in fact outwitted Carker, playing him to her purposes. While clever, this scheme has deep consequences for Edith in that her reputation is ruined and she will never be socially accepted again. Her sense of shame and moral disgust has become a kind of self-fulfilling prophecy. And yet, Edith is willing to tolerate this because she is free and will no longer have to live a lie. The Dombey household dynamic was so poisonous for both Edith and Florence that even the drastic risks they take in liberating themselves are presented as worthwhile.