A Doll’s House opens on Christmas Eve. Nora Helmer enters her well-furnished living room—the setting of the entire play—carrying several packages. Torvald Helmer, Nora’s husband, comes out of his study when he hears her arrive. He greets her playfully and affectionately, but then chides her for spending so much money on Christmas gifts. Their conversation reveals that the Helmers have had to be careful with money for many years, but that Torvald has recently obtained a new position at the bank where he works that will afford them a more comfortable lifestyle.

Helene, the maid, announces that the Helmers’ dear friend Dr. Rank has come to visit. At the same time, another visitor has arrived, this one unknown. To Nora’s great surprise, Kristine Linde, a former school friend, comes into the room. The two have not seen each other for years, but Nora mentions having read that Mrs. Linde’s husband passed away a few years earlier. Mrs. Linde tells Nora that when her husband died, she was left with no money and no children. Nora tells Mrs. Linde about her first year of marriage to Torvald. She explains that they were very poor and both had to work long hours. Torvald became sick, she adds, and the couple had to travel to Italy so that Torvald could recover.

Nora inquires further about Mrs. Linde’s life, and Mrs. Linde explains that for years she had to care for her sick mother and her two younger brothers. She states that her mother has passed away, though, and that the brothers are too old to need her. Instead of feeling relief, Mrs. Linde says she feels empty because she has no occupation; she hopes that Torvald may be able to help her obtain employment. Nora promises to speak to Torvald and then reveals a great secret to Mrs. Linde—without Torvald’s knowledge, Nora illegally borrowed money for the trip that she and Torvald took to Italy; she told Torvald that the money had come from her father. For years, Nora reveals, she has worked and saved in secret, slowly repaying the debt, and soon it will be fully repaid.

Krogstad, a low-level employee at the bank where Torvald works, arrives and proceeds into Torvald’s study. Nora reacts uneasily to Krogstad’s presence, and Dr. Rank, coming out of the study, says Krogstad is “morally sick.” Once he has finished meeting with Krogstad, Torvald comes into the living room and says that he can probably hire Mrs. Linde at the bank. Dr. Rank, Torvald, and Mrs. Linde then depart, leaving Nora by herself. Nora’s children return with their nanny, Anne-Marie, and Nora plays with them until she notices Krogstad’s presence in the room. The two converse, and Krogstad is revealed to be the source of Nora’s secret loan.

Krogstad states that Torvald wants to fire him from his position at the bank and alludes to his own poor reputation. He asks Nora to use her influence to ensure that his position remains secure. When she refuses, Krogstad points out that he has in his possession a contract that contains Nora’s forgery of her father’s signature. Krogstad blackmails Nora, threatening to reveal her crime and to bring shame and disgrace on both Nora and her husband if she does not prevent Torvald from firing him. Krogstad leaves, and when Torvald returns, Nora tries to convince him not to fire Krogstad, but Torvald will hear nothing of it. He declares Krogstad an immoral man and states that he feels physically ill in the presence of such people.

Act Two opens on the following day, Christmas. Alone, Nora paces her living room, filled with anxiety. Mrs. Linde arrives and helps sew Nora’s costume for the ball that Nora will be attending at her neighbors’ home the following evening. Nora tells Mrs. Linde that Dr. Rank has a mortal illness that he inherited from his father. Nora’s suspicious behavior leads Mrs. Linde to guess that Dr. Rank is the source of Nora’s loan. Nora denies Mrs. Linde’s charge but refuses to reveal the source of her distress. Torvald arrives, and Nora again begs him to keep Krogstad employed at the bank, but again Torvald refuses. When Nora presses him, he admits that Krogstad’s moral behavior isn’t all that bothers him—he dislikes Krogstad’s overly familiar attitude. Torvald and Nora argue until Torvald sends the maid to deliver Krogstad’s letter of dismissal.

Torvald leaves. Dr. Rank arrives and tells Nora that he knows he is close to death. She attempts to cheer him up and begins to flirt with him. She seems to be preparing to ask him to intervene on her behalf in her struggle with Torvald. Suddenly, Dr. Rank reveals to Nora that he is in love with her. In light of this revelation, Nora refuses to ask Dr. Rank for anything.

Once Dr. Rank leaves, Krogstad arrives and demands an explanation for his dismissal. He wants respectability and has changed the terms of the blackmail: he now insists to Nora not only that he be rehired at the bank but that he be rehired in a higher position. He then puts a letter detailing Nora’s debt and forgery in the Helmers’ letterbox. In a panic, Nora tells Mrs. Linde everything, and Mrs. Linde instructs Nora to delay Torvald from opening the letter as long as possible while she goes to speak with Krogstad. In order to distract Torvald from the letterbox, Nora begins to practice the tarantella she will perform at that evening’s costume party. In her agitated emotional state, she dances wildly and violently, displeasing Torvald. Nora manages to make Torvald promise not to open his mail until after she performs at the party. Mrs. Linde soon returns and says that she has left Krogstad a note but that he will be gone until the following evening.

The next night, as the costume party takes place upstairs, Krogstad meets Mrs. Linde in the Helmers’ living room. Their conversation reveals that the two had once been deeply in love, but Mrs. Linde left Krogstad for a wealthier man who would enable her to support her family. She tells Krogstad that now that she is free of her own familial obligations and wishes to be with Krogstad and care for his children. Krogstad is overjoyed and says he will demand his letter back before Torvald can read it and learn Nora’s secret. Mrs. Linde, however, insists he leave the letter, because she believes both Torvald and Nora will be better off once the truth has been revealed.

Soon after Krogstad’s departure, Nora and Torvald enter, back from the costume ball. After saying goodnight to Mrs. Linde, Torvald tells Nora how desirable she looked as she danced. Dr. Rank, who was also at the party and has come to say goodnight, promptly interrupts Torvald’s advances on Nora. After Dr. Rank leaves, Torvald finds in his letterbox two of Dr. Rank’s visiting cards, each with a black cross above the name. Nora knows Dr. Rank’s cards constitute his announcement that he will soon die, and she informs Torvald of this fact. She then insists that Torvald read Krogstad’s letter.

Torvald reads the letter and is outraged. He calls Nora a hypocrite and a liar and complains that she has ruined his happiness. He declares that she will not be allowed to raise their children. Helene then brings in a letter. Torvald opens it and discovers that Krogstad has returned Nora’s contract (which contains the forged signature). Overjoyed, Torvald attempts to dismiss his past insults, but his harsh words have triggered something in Nora. She declares that despite their eight years of marriage, they do not understand one another. Torvald, Nora asserts, has treated her like a “doll” to be played with and admired. She decides to leave Torvald, declaring that she must “make sense of [her]self and everything around her.” She walks out, slamming the door behind her.