The scene begins half an hour after the previous scene. The family is returning from lunch in the dining room. Tyrone appears angry and aloof, while Edmund appears "heartsick." Mary and Tyrone argue briefly about the nature of the "home," although Mary seems somewhat aloof while she speaks because she is on morphine. The phone rings, and Tyrone answers it. He talks briefly with the caller and agrees on a meeting at four o'clock. He returns and tells the family that the caller was Doc Hardy, who wanted to see Edmund that afternoon. Edmund remarks that it doesn't sound like good tidings. Mary immediately discredits everything Doc Hardy has to say because she thinks he is a cheap quack whom Tyrone hired only because he is inexpensive. After a brief argument, she exits upstairs.
After she is gone, Jamie remarks that she has gone to get more morphine. Edmund and Tyrone explode at him, telling him not to think such bad thoughts about people. Jamie counters that Edmund and Tyrone need to face the truth; they are kidding themselves. Edmund tells Jamie that he is too pessimistic. Tyrone argues that both boys have forgotten Catholicism, the only belief that is not fraudulent. Jamie and Edmund both grow mad and begin to argue with Tyrone. Tyrone admits that he does not practice Catholicism strictly, but he claims that he prays each morning and each evening. Edmund is a believer in Nietzsche, who wrote that "God is dead" in ##Thus Spoke Zarathustra# He ends the argument, however, by resolving to speak with Mary about the drugs, and he exits upstairs.
After Edmund leaves, Tyrone tells Jamie that Doc Hardy say that Edmund has consumption, "no possible doubt." However, if Edmund goes to a sanatorium immediately, he will be cured in six to 12 months. Jamie demands that Tyrone send Edmund somewhere good, not somewhere cheap. Jamie says that Tyrone thinks consumption is necessarily fatal, and therefore it is not worth spending money on trying to cure Edmund since he is guaranteed to die anyway. Jamie correctly argues that consumption can be cured if treated properly. He decides to go with Tyrone and Edmund to the doctor that afternoon then exits.
Mary reenters as Jamie leaves, and she tells Tyrone that Jamie would be a good son if he had been raised in a "real" home as Mary envisions it. She tells Tyrone not to give Jamie any money because he will use it only to but liquor. Tyrone bitterly implies that Mary and her drug use is enough to make any man want to drink. Mary dodges his accusation with denials, but she asks Tyrone not to leave her alone that afternoon because she gets lonely. Tyrone responds that Mary is the one who "leaves," referring to her mental aloofness when she takes drugs. Tyrone suggests that Mary take a ride in the new car he bought her, which to Tyrone's resentment does not often get used (he sees it as another waste of money). Mary tells him that he should not have bought her a second-hand car. In any case, Mary argues that she has no one to visit in the car, since she has not had any friends since she got married. She alludes briefly to a scandal involving Tyrone and a mistress at the beginning of their marriage, and this event caused many of her friends to abandon her. Tyrone tells Mary not to dig up the past. Mary changes the subject and tells Tyrone that she needs to go to the drugstore.
Delving into the past, Mary tells Tyrone the story of getting addicted to morphine when Edmund was born. She implicitly blames Tyrone for her addiction because he would only pay for a cheap doctor who knew of no better way to cure her childbirth pain. Tyrone interrupts and tells her to forget the past, but Mary replies, "Why? How can I? The past is the present, isn't it? It's the future too. We all try to lie out of that but life won't let us." Mary blames herself for breaking her vow never to have another baby after Eugene, her second baby who died at two years old from measles he caught from Jamie after Jamie went into the baby's room. Tyrone tells Mary to let the dead baby rest in peace, but Mary only blames herself more for not staying with Eugene (her mother was babysitting when Jamie gave Eugene measles), and instead going on the road to keep Tyrone company as he traveled the country with his plays. Tyrone had later insisted that Mary have another baby to replace Eugene, and so Edmund was born. But Mary claimed that from the first day she could tell that Edmund was weak and fragile, as though God intended to punish her for what happened to Eugene.
Edmund reenters after Mary's speech, and he asks Tyrone for money, which Tyrone grudgingly produces. Edmund is genuinely thankful, but then he gets the idea that Tyrone may regret giving him money because Tyrone thinks that Edmund will die and the money will be wasted. Tyrone is greatly hurt by this accusation, and Edmund suddenly feels very guilty for what he said. He and his father make amends briefly before Mary furiously tells Edmund not to be so morbid and pessimistic. She begins to cry, and Tyrone exits to get ready to go to the doctor with Edmund. Mary again criticizes Doc Hardy and tells Edmund not to see him. Edmund replies that Mary needs to quit the morphine, which puts Mary on the defensive, denying that she still uses and then making excuses for herself. She admits that she lies to herself all the time, and she says that she can "no longer call my soul my own." She hopes for redemption one day through the Virgin. Jamie and Tyrone call Edmund, and he exits. Mary is left alone, glad that they are gone but feeling "so lonely."