Rivers is introduced to Prior, a new patient in the hospital who refuses to speak. Prior writes on a pad, in block letters only, saying that he does not remember what happened to him and that there is nothing physically wrong with him. He is hostile to Rivers.
Sassoon says goodbye to Graves and leaves the hospital for a short walk through the town. Despite what Rivers has said about Sassoon hating safety, Sassoon is happy to go to bed each night in white sheets knowing that he will wake the next morning.
Rivers goes home and prepares his nightly bath. He constantly thinks about the hospital and the welfare of his patients. He resents the luxury Sassoon has to object to the war. Though Rivers wants nothing more than for the war to end so that he may return to his research in Cambridge, he understands that it should not be left to another generation to fight German militarism.
Rivers goes to sleep. Later he wakes from a nightmare and record what happened in his dream. He dreamt that he was recording the hypersensitivity to pain on the arm of his friend Henry Head. To his surprise, Head suddenly turned the scalpel on him and jabbed it into Rivers's own arm. Rivers realizes what the content of his dream was about. Years ago, he had been working with Head on research to study nerve regeneration after accidental injury. Head offered himself as the subject of study, and Rivers assisted him in severing the radial nerve, suturing it back together, and recording the growth over a five-year period. The essence of his dream is his strong feeling of dislike of inflicting pain.
Rivers concludes that the dream must refer to his aversion against inflicting any pain on his patients. By encouraging his patients to talk about their traumatic experiences, Rivers forces them to relive their pain. Furthermore, as this method is experimental, he does not even know if this is helping them. Rivers realizes that by encouraging his patients to express their feelings, he weakens the basis of manliness upon which both he and they have been raised.
The next morning, Rivers speaks with Prior, who has gotten his voice back in the night. He says that his voice comes and goes, but he does not know why. Prior is a difficult patient; he does not want to talk about his dreams or his experiences because he sees no reason to churn up memories. When Rivers gets up to leave, Prior becomes more cooperative. He tells Rivers a little about what he remembers. In the war, he would have to stand in a dugout in No Man's Land—the neutral ground between the English and German trenches—for forty-eight hours at a time, just to "protect" the land. The Germans would do their best to bomb the men in the hole the entire time. The last thing Prior remembers is being carried out of the hole.
Rivers then meets with Sassoon for their scheduled appointment. Sassoon claims Bertrand Russell did not influence him, and that his first introduction to pacifism was several books by a man named Edward Carpenter. Sassoon is a great fan of Carpenter, who also wrote a book called The Intermediate Sex. Sassoon skirts around the issue, but implies that he is a homosexual. Rivers claims to be familiar with that book as well (his sexuality is unknown). Rivers advises Sassoon to be careful about letting his secret out, as there are many people who would use his personal life to discredit his political views.
Mr. Prior, Billy Prior's father, comes in to see Rivers. Mr. Prior has nothing but contempt for his son. He thinks that his mother made him too ambitious, and now he is ruined. He is not happy that his son joined the army or became an officer; he thinks Billy should have stayed with his own class. Mr. Prior says he would have more sympathy for his son if he had been hit by a bullet. After Mr. Prior leaves, Mrs. Prior comes in to talk to Rivers. She has much sympathy for her son, and she tells Rivers much about their personal life. She believes that Billy blames her for trying to better him and separate him from the "common people." Mr. Prior resents his son's education, and Mrs. Prior senses competition between them.
Mr. Broadbent, another patient, comes to see Rivers and ask him for a leave of absence, as his mother is sick. Rivers doubts that there is any sick mother, as Broadbent is known for doing things in the hospital just to get attention. He tells Broadbent to speak with Bryce about it. Rivers is frustrated by all these interruptions.
Later that night, Rivers finds Prior watching the cinema on the first floor of the hospital. His asthma is very bad, and his wheezing is loudly audible. Rivers brings Prior into the sick bay to examine him. Prior tells Rivers that he did not want his father to come barging in as he did. Prior does not like his father, who he admits used to hit his mother when Prior was too young to stop it. Prior says his asthma was better in France than it ever was at home.
Emasculation is a motif that runs throughout Regeneration. Anderson dreams he is tied up with corsets; Sassoon remembers the boy whose genitals were shot off in the war; Prior recalls his weakness against his father and the influence of his mother; Rivers counsels Sassoon on homosexuality and the idea of an "intermediate sex." All of these patients fear emasculation—a real threat in the war and a real threat in the war hospital. As patients, they turn over all power to the doctors and nurses who care for them, most notably Dr. Rivers. Rivers worries about this effect of powerlessness upon his patients; not only are the patients fully under his control, but also his very method of therapy appears to be an emasculating one. Rivers hopes to cure his patients by forcing his patients to talk about their fears, their memories, their families, whatever is bothering them. He recognizes that talking about their feelings goes against the "whole tenor of their upbringing." He acknowledges that "they had been trained to identify emotional repression as the essence of manliness." If they let go of this repression, they might associate with being twice emasculated. This is Prior's main problem; he resists Rivers's method because, as a boy, he was trained to be as masculine as possible. He would even rather undergo hypnosis—a physical submission—than release his feelings in what he sees as an emotional submission. Rivers wrestles with the costs and benefits of his method; is it worth it to potentially "cure" his patients if the cost is emotional castration? Should he challenge the traditional definitions of masculinity? Rivers decides to continue with the treatment.