This book opens up with James and Mary Tyrone talking. They seem to be a very loving, married couple. James compliments Mary many times about how beautiful she looks. However she seems to be insecure about her looks because she is discontent with her case of rheumatism in her hands which makes it shake all the time. Then they heard their two sons laughing, as they walk out from the dinning room. As Edmund and Jamie enter, their parents question them what they are talking about.
Edmund tells the story of Harker and Shaughnessy, which he had heard from the night before. Then afterwards Edmund and Mary leave the scene, and only James and Jamie is having a conversation. They seemed worried about Edmund who is sick with a "cold," so they hoped, but in reality they know it's not just that. They are also worried about Mary, but it is not yet revealed what is wrong with her. James and Jamie then leave to go work out on the hedge as Mary and Edmund begins to talk.
They show a loving mother and son bond, they both care a lot about each other's health. After their talk, Mary went upstairs to rest as Edmund remained in the parlor reading. Continuing to the next scene, James and Jamie comes in from outside for lunch. They must wait a while though because James was still talking to Captain Turner. Jamie seems to imply that his mother is doing something that she has done in the past that wasn't too good for her, but it doesn't indicate what it is yet. Then James comes in and also says that something is wrong with her, but does not say what it is.
He just say that he that why didn't she have the strength to keep on, but Mary acts as if she does not know what he is talking about. After lunch, they all follow Mary back into the parlor. Mary is talking about how their home is not really a home, and then the phone rings. It is Dr. Hardy. He has called for Edmund to come up to the office to see him that afternoon.
When Edmund and Mary leaves the scene, James and Jamie begins talking about what the Doctor said. Hardy told James that it was sure that Edmund had "consumption," and must be sent to a sanatorium, which will cure him in a year. Jamie then says he " ll go uptown with Edmund; he then leaves the room to go get dressed. Now Mary comes back.
Edmund hints again about something being wrong with Mary, and then Mary finally blurts out what has been wrong with her. She speaks of how it is her fault that Edmund is sick, because God is punishing her for Eugene's, her baby's, death. She has not gotten over that because she blames herself for leaving him and going with James when she was younger. While she was away Jamie, who had the measles, went into Eugene's room and caused Eugene to die.
James tries to leave, but she asks him to stay because she does not want o be alone. Eventually he does leave because Edmund comes in. at this point, Mary seems to be acting very strangely and emotional. Finally, Edmund, Jamie, and James leave the house to go uptown. As Mary stands at home alone, and waits for her family to come home, she talks to Cathleen. She tells Cathleen of her past; how she was when she was young, her life as a child, and how she met James.
Cathleen wasn't really excited to hear the story and kept trying to leave but couldn't for a while. Finally, James and Edmund had come home. The all sit in the parlor and wait till dinner. Mary keeps on talking, even though it seems that nobody is even listening, and many times James and Edmund tried to change the subject but couldn't. She spoke mainly of her past and how her father spoiled her. Then finally James suggested they go have dinner, but Mary says that she's not hungry, she's just going to go upstairs and rest.
James accuses her of going to take her "poison" because she keeps taking this medicine. Finally in the last Act, Edmund comes home drunk and he begins to quarrel with his father. He tries to drink but because of his health, James does not want him to drink, but Edmund does not except this, and they argue some more. Then later Jamie comes home drunk.
Edmund asks him to give him a drink; Jamie refuses and says that he loves him to much to let him die. After that Mary comes in and tries to play the piano again, but cannot because he fingers are stiff. She tries to relive her past, and brought with her the wedding gown but says she wants to be a nun. Edmund reveals to her that he has consumption, and she refuses but then goes back into the trance, and her family just gives up trying to reach her while she is still under the medicine's effects.