The day after the party, Peter makes an arrangement with the local farmer, Mr. Paul, so that Mary and Jennifer will be able to get milk and cream while he is away at sea. Dwight goes to church by himself to think about his family in America. Even though they have obviously been killed in the war along with everyone else in the United States, Dwight refuses to accept the fact that they are dead. He thinks about buying a fishing rod as a tenth- birthday present for his son, Junior, and thinks about seeing his daughter, Helen, again when he returns to America in September.
Upon returning to Peter's home, Dwight talks with Moira. She speaks about how bored she is with life, with nothing but drinking to keep her busy. Dwight remarks that he is lucky to have a job to occupy his time. He invites her to visit the submarine, and she asks for an exact date so she will have something to look forward to. Dwight teases her not to mix whiskey and brandy again, but she says it is her body so she can do whatever she wants to it. Moira goes home and tells her mother about meeting Dwight. Moira is annoyed by her mother's questions, but she resists the urge to argue with her mother when she considers how little time is left.
Meanwhile, Dwight goes to the Navy Department and meets with John Osborne, an Australian civilian scientist. John has never been on a submarine before. His job on this mission will be to make observations and take readings of the radiation levels both in and above the water. He is to alert the crew if the radiation levels rise within the sub.
From Tuesday to Friday of that week, the crew conducts a trial run of the submarine. On Saturday, Moira visits the ship. She goes into Dwight's sleeping cabin to change into a pair of overalls; inside the room, she sees photos of Dwight and his family. It was hard for Moira to look at them. Dwight's wife and children look like nice people, but she sees no use agonizing over it.
Dwight tells Moira that the submarine will go north, up the coast of Australia, to see if anyone there is still alive. Moira asks Dwight if he can visualize the cities in North America, a place she has never visited. He says he prefers to remember them as they were before the war. He admits that no one but God will know what the cities now look like.
Desperate to get away from the morbid reality, Moira suggests going drinking and dancing in Melbourne. Most of the stores in the city are closed, but the restaurants and cafés are packed. The bars are closed, but the streets are nonetheless full of drunks. Moira speaks again about how Dwight is lucky to have a job. The only work she does is helping on her father's farm. Before the war, she had finished university and had been planning to take secretarial courses. Moira does not see any reason to take the courses now, considering she would not have time to finish them and there are no jobs available anyway. Dwight suggests she work for the sake of working. When they part company, he thinks to himself how Moira reminds him a little of his wife, Sharon, and perhaps that is why he likes Moira so much.
The next day, Dwight goes to church. He then meets with some other officers and the Prime Minister of Australia, who gives the details of the Scorpion's mission. Dwight is warned not to surface the submarine near Townsville, a town in northern Australia. If people are still alive there and see the ship, it would only give them false hope.
The extreme events that have preceded the novel have shifted the characters' definition of sanity. Dwight is a thoroughly practical man, yet he still believes his family is alive and waiting for him in America. He is emotionally incapable of admitting to a rational awareness of their deaths. Delusion has become a practical means to cope with the enormous tragedy of the situation. Dwight can continue to function only as long as he continues to believe his family is alive. At this point in the novel, Dwight seems alone in his insanity, but soon we see nearly all the characters demonstrate a resistance to believe and accept the situation. Shute subtly introduces religion in this chapter, but he never gives it the attention we might expect in a novel about the end of the world. Dwight uses the church as a quiet place to daydream about his family, not as a place to pray. He finds more comfort in the familiar look and smell of the church than in the prayers. The Holmeses do not attend church, but they mention that more people go to services than ever before.
The characters in On the Beach find salvation in work rather than religion. As soon as Dwight leaves the church, he turns his thoughts toward the work to be done on the submarine. As in many of Shute's novels, the characters are always at work—in this case, working until the last day of humanity. Work serves as a distraction and a break from the tedium of waiting for the world to end. It also serves as a safe alternative to more destructive human habits, such as excessive drinking. Moira keenly observes Dwight's workaholic tendencies while admitting her alcoholic tendencies. A double brandy is her ticket to a world of romance and make-believe. She admits she might not drink as much if she had someone in her life who cared about what she did to her body. Dwight does not respond to Moira's advance because he still believes his wife is alive and waiting for him.
Moira's desire to escape the morbid reality contrasts sharply with John Osborne's fascination with studying the radiation. John's reaction to the situation is emblematic of the way the scientific community as a whole responds to the disaster. While we might expect the scientists to be horrified about the war their technologies have helped create, they instead continue to objectively conduct experiments. John declares that he will enjoy discovering the effects of radiation poisoning, not considering the moral and ethical implications of his words or actions. It is this same scientific objectivity and detachment that made it possible for researchers to create the bombs in the first place. John is Shute's alter ego in many ways. From his own life experience as an engineer, Shute understands the minds of scientists and engineers who create weapons of war. Moira responds sarcastically to John's shocking comments, but Shute never fully criticizes John for his viewpoint. Shute writes like an objective scientist, observing human behavior but not criticizing it—leaving us to draw our own moral and ethical conclusions.