Over dinner at the Oblonskys’, a guest makes a remark that displeases Karenin, who leaves the table. He finds Dolly in the drawing room and reveals to her his firm plans for divorce. Hearing that Anna has cheated on Karenin, Dolly protests that Anna will be ruined. Karenin claims there is nothing he can do.
At the same dinner, Levin and Kitty speak to each other for the first time since her rejection of his marriage proposal. Clearly still caring for each other greatly, they play a word game on a card table through which they apologize to each other for their past errors. Levin proposes to Kitty again, and she accepts. Later, Levin tells his brother Sergei of his engagement and wanders sleeplessly in the streets, overjoyed. When morning comes, Levin visits the Shcherbatsky house and embraces Kitty. In a happy daze, Levin goes off to buy flowers and presents for the engagement celebration. Levin, wishing to be fully honest with Kitty, shows her his journals, which divulge the fact that he is agnostic and has not been chaste prior to marriage. Kitty is upset but ultimately forgiving.
Karenin is passed over for a government post he has been coveting. Just after receiving this bad news, he receives a telegram announcing that Anna is gravely ill. He arrives to learn that Anna has delivered a baby girl, and that she is suffering from a fever from which she is not expected to recover. Vronsky is present at Anna’s bedside. Anna is sure she is dying, so she begs Karenin for forgiveness. She also implores Karenin to forgive Vronsky, which Karenin tearfully does.
When Vronsky is about to leave the house, Karenin tells him that he has forgiven Anna and will stay by her side. Vronsky departs with the feeling that his love for Anna, which has flagged lately, is reviving. Back at his home, he cannot sleep, tormented by the possibility of Anna’s death. Only half-aware of his actions, Vronsky aims a pistol at his chest and fires. He is gravely wounded but survives, as one of his servants quickly discovers him and sends for doctors.
Karenin, meanwhile, is surprised by how sincerely he was able to forgive Anna, and by the tenderness he feels toward her newborn daughter, who is also named Anna. Later, Karenin overhears a conversation between Anna and Betsy Tverskaya. Betsy implores Anna to say goodbye to Vronsky before he leaves for the provincial capital of Tashkent, where he is to be stationed. Anna refuses, saying that there is no point in seeing Vronsky again. On the way out, Betsy begs Karenin to allow Vronsky to visit Anna one last time. Karenin answers that such a matter is solely his wife’s decision. In desperate grief, Anna privately affirms to Karenin that there is no point in seeing Vronsky again. Karenin says he is willing to allow the affair to continue, provided that the family and children are not disgraced.
Stiva arrives at the Karenin house. Anna privately tells him that she cannot stand Karenin any longer. Stiva says the problem is simple: Anna married someone whom she did not love and who was twenty years her senior; now she loves another man, and she must decide whether or not to stay with her husband. Anna says she does not know what to do. Stiva speaks to Karenin, who shows him a letter he has begun writing to Anna. The letter tells Anna that the decision about the future of their marriage is entirely in her hands. Stiva says that only divorce will satisfy Anna, but Karenin reminds him of the disgrace she will suffer if she chooses such a path. Stiva mentions that Karenin could allow Anna to escape public shame by taking responsibility for the disgrace himself—by pretending that it was he, rather than Anna, who committed adultery. Karenin tearfully says that he is willing to accept this option.