Dr. Rivers is completing his last evening rounds at Craiglockhart before leaving for his new position in London. Willard, the soldier who was paralyzed below the waist, has begun walking again, though he credits his recovery to a surgical intervention by the psychologist instead of admitting that his condition was mental. At the end of his rounds, Dr. Rivers meets with Sassoon and notices that the lieutenant seems subdued, as if he has “given up hope of influencing events” (221). Sassoon has come from a meeting with a famous pacifist who has scolded him for agreeing to participate in the war again. Dr. Rivers advises Sassoon to avoid getting into further trouble before his rescheduled board review.
The psychologist moves into a boarding house in London, where the constant air raids interfere with his sleep. Dr. Rivers begins to feel increasingly ill in the sinister setting of war-time London. At his new position, he studies the incidence of shell-shock in different branches of the Royal Flying Corps, discovering that men who pilot observation balloons have the highest rate of breakdowns. The soldiers are trapped in the balloons without any ability to attack or defend themselves, leaving them helpless, which induces shell-shock. Dr. Rivers compares the immobilized soldiers to women during peace time, whose prescribed social roles leave them helpless and vulnerable to bouts of hysteria. In addition to his new work, Dr. Rivers remains in touch with many of his former patients.
Eventually, Dr. Rivers accepts an invitation to visit Queen Square Hospital, where one of his colleagues, Dr. Yealland, is using extreme physical methods to achieve results in shell-shocked patients. When Rivers arrives, he walks down an eerily silent corridor that reminds him of his patients’ descriptions of "No Man’s Land." Along the way, he encounters a horribly disfigured man who gives the psychologist a disturbing look.
Dr. Yealland and an entourage of doctors and nurses walk over to meet Dr. Rivers. Dr. Yealland is aggressive and authoritarian, relishing the power he holds over patients. The men under his care seem depressed, but Dr. Yealland does not care much about their mental well-being. Unlike Rivers, Yealland is interested in conducting strictly in one-time, physical treatments. The group walks through the wards and arrives at the bed of the disfigured man that Dr. Rivers spied in the hallway. Yealland speaks about this patient clinically, as if he were a specimen to be dissected and repaired. When the patient expresses fear of the painful treatments the doctor has planned for him, Yealland condescendingly silences him in an “almost God-like tone” (226).
The group moves on to another patient named Callan who suffers from mutism. Dr. Yealland accuses Callan of having a poor attitude. Meanwhile, another doctor describes the horrific medical treatments to which Callan has been subjected, including having lit cigarettes pushed into his tongue and being shocked with electrodes. Dr. Rivers is taken aback by the extreme nature of the so-called cures and is interested in witnessing a one of Dr. Yealland's sessions with Callan. Dr. Yealland reveals that he only has one private session with each patient and does not allow them to leave until he deems them cured. Dr. Yealland warns Rivers that Callan’s session could last for an extended period of time, given his anti-authoritarian nature. Dr. Rivers understands and agrees to stay for the entire treatment.
After lunch, Dr. Yealland prepares to treat Callan, seemingly enthusiastic about the task. Rivers follows Yealland into a room that is pitch-black except for a small light illuminating a battery powering the electroshock machine. In the center of the room sits what looks like a dentist’s chair with restraining straps. Dr. Rivers finds an inconspicuous seat against a far wall. As he is strapped into the chair, Callan is filled with fear and apprehension. Dr. Yealland informs Callan that the door is locked and he will only be allowed to leave once he speaks as well as he did before becoming mute.
Dr. Yealland pushes an electrode into the back of Callan’s throat, causing the patient to spasm from the force of the shock. He keeps shocking Callan repeatedly for over an hour, until the soldier produces a small “ah” (230). Dr. Yealland is pleased, lording over his patient and insisting that he has complete control over him. Yealland then forces Callan to march around the battery, even though the man is exhausted and near collapse. Afterwards, Callan resignedly motions for the doctor to continue his treatment. Dr. Yealland informs Callan that he has no control over when the treatment will begin again: the timing and frequency of the shocks are subject only to the doctor’s whim. Dr. Rivers is horrified watching Callan struggle to speak, remembering his own difficulties with stammering.
After another round of shocks, Callan is able to produce a “bah” sound before he collapses in tears (232). He asks for water and then attempts to break out of the room, pounding on the locked door. Dr. Yealland condescendingly informs Callan that he must live up to his status as a war hero before turning up the current to resume the treatment. Eventually, after several hours, Callan begins tentatively forming words, then phrases, and eventually, fully-formed sentences. At the end of the session, Callan smiles in a way that irritates Dr. Yealland; the doctor forces him back into the chair and shocks his mouth to take the smile off his face. Callan, completely broken, thanks Dr. Yealland as he leaves.
That night, Dr. Rivers is haunted by images of the "treatment" he witnessed, describing his memories of the incident as “hallucinatory” (234). He is distracted and unable to work on his upcoming paper, so he leaves his room to walk around a darkened London. Even then, the images from the afternoon will not leave his thoughts; the psychologist eventually returns home and goes to bed.
Dr. Rivers dreams that he is walking down the eerie corridor of Queen Square Hospital, where he runs into the disfigured patient from that morning. The man is chanting the first lines of Sassoon’s letter protesting the war. Suddenly, Rivers finds himself with an electrode in his hand and a man’s open mouth in front of him. Dr. Rivers attempts to push the electrode into the patient’s mouth, but it is too big. He realizes that the electrode has metamorphosed into a horse bit, which he is cruelly jamming into the patient’s mouth. The psychologist is awoken by his own scream, deeply disturbed by the images his brain has created.
Dr. Rivers notes that though his dream featured a scene of “oral rape,” it did not feel sexual (236). He traces the dream to his discomfort with Dr. Yealland's methods; Rivers recalls that his own stutter had been getting worse throughout the day. Dr. Rivers speculates that the disfigured man in his dream must represent Sassoon, since he was reciting his letter, but he cannot figure out who the second patient (into whose mouth he was forcing the horse bit) could represent.
Rivers remembers that he once scraped a spoon across the back of Prior’s throat to try and induce speech and feels disgusted with himself. Suddenly, Rivers feels as though there is no difference between him and Dr. Yealland: both men are tasked with pushing ill men back into a deadly situation that they are trying desperately to escape. The silence of men like Callan and Prior is their protest against an unjust system, Rivers muses, and the doctors are the ones silencing the soldiers' protest by forcing them to speak. Trying but failing to avoid the realization, Dr. Rivers discovers the identity of the man he silenced and therefore, was seated in the dentist’s chair in his dream: Sassoon.
Henry Head assures Dr. Rivers that he is nothing like Dr. Yealland. He adds that Sassoon’s integrity would have prevented him from staying at Craiglockhart once his protest failed, regardless of the psychologist’s actions. Dr. Rivers expresses his worry that Sassoon is returning to war in order to die, citing his lack of concern about the future.
However, Rivers also realizes that treating Sassoon has changed his life. He recounts another incident that has had a large impact on his perspective. He explains to Head that when he was traveling in the Solomon Islands, he mapped kinship networks and cultural practices by asking people what they would do with a large windfall of money. Eventually, the native people turned the question around and asked Dr. Rivers what he would do with the same riches. The psychologist was forced to admit that he didn’t have anyone to share the money with, which struck the islanders as absurd. This forced Rivers to realize both how lonely he was and the inherent contrivance of systematic English superiority. Native habits were as strange to Rivers as his English habits were to the natives. In the aftermath of that conversation, Dr. Rivers decided to embrace cultural relativism and to try to connect more with others.
Dr. Rivers returns to Craiglockhart for Anderson and Sassoon’s board hearings. He briefly meets with each soldier, noting that Anderson has grown more dependent and Sassoon more resigned. Meanwhile, Sassoon reveals that he suspects Owen has developed something more than platonic feelings for him. During Anderson's board hearing, Rivers helps to secure the (former) doctor a position in the War Office bureaucracy, away from the blood of either the battle field or a civilian medical practice. Next, Dr. Rivers argues to the board that Sassoon should return to the front because he has renounced his dangerous ideas. When interviewed, however, Sassoon denies that he has changed his opinion about the war, emphasizing that he holds his ideals firmer than ever. Nevertheless, the lieutenant insists on returning to France. Given his talents and his fitness, both physical and emotional, the board agrees to let Sassoon go.
After the hearing, Sassoon and Dr. Rivers meet to say goodbye. The psychologist tells Sassoon that he can blame his decision to return on him, but Sassoon rejects the offer. The lieutenant admits that he lied to the board about no longer having nightmares, explaining that they have actually intensified since Dr. Rivers’s departure. Dr. Rivers tells him not to take unnecessary risks, but Sassoon thinks to himself that he might. They part on good but depressing terms. As he is leaving, Sassoon thanks the board members, instantly reminding Dr. Rivers of Callan thanking Dr. Yealland.
As he fills out the day’s paperwork, Dr. Rivers marvels as to how much Sassoon has changed him, even though it was the doctor who was tasked with changing Sassoon. After treating Sassoon, Rivers now rejects the military values he once championed, concluding, “a society that devours its own young deserves no automatic or unquestioning allegiance” (249). The psychologist ponders the contradiction between Sassoon’s hardened pacifism and his desire to return to war and becomes more convinced than ever that Sassoon’s decision is not just a juvenile rebellion against authority, but rather, the reflection of a “genuine and very deep desire for death” (250). The doctor thinks that if Sassoon does not die he will have a serious mental breakdown. He flips through to Sassoon’s file and finds that he can write nothing more about this man than “Nov. 26, 1917. Discharged to duty” (250).
In Chapter 20, Barker introduces Dr. Yealland, an aggressive and domineering doctor with a distinct lack of sympathy for his patients’ suffering. Yealland uses one-time, extreme treatments on afflicted men before abandoning them completely: he admits that he does not know how many of his former patients relapse or commit suicide. Dr. Yealland embodies Sassoon’s most cutting critiques about the British government: the man funnels human lives into the thresher of war without any sympathy. Moreover, he revels in his authority, viewing himself as a God-like figure. His gleeful behavior during Callan's session indicates that Yealland is not simply administering treatment, but also getting sadistic enjoyment out of dominating another human being. Indeed, he pushes an electrode into Callan’s face at the end of the session, not to address any speech problem, but simply to punish him for smiling. His treatment leaves the soldier completely broken and humiliated.
While Dr. Yealland’s technique is the opposite of Dr. Rivers's compassionate approach, Yealland's extreme behavior helps Dr. Rivers to understand his own role in silencing his patients. The psychologist realizes that, like Dr. Yealland, he has gained control over men in order to change their behavior and send them back to a brutal and bloody war. In his dream, Dr. Rivers attempts to shove a horse’s bit, a tool used to control horses, into a patient’s mouth, which symbolizes his waking desire to direct his patients' behavior. The psychologist cringes, remembering the time he scraped the back of Prior’s throat, trying to induce him to speak. Dr. Yealland’s uncaring behavior further highlights the irony implicit in being a war doctor: through he is nurturing and healing, Dr. Rivers is condemning his patients to injury, trauma, and death. Specifically, Dr. Rivers has been complicit in silencing Sassoon by pushing him back into battle, where he will endanger his life once again for a cause in which he does not believe. In the novel’s final chapter, Sassoon thanks his tormentors on the board, much like Callan thanks Dr. Yealland. He is breaking - and Dr. Rivers realizes that he has played a crucial role in Sassoon's current state.
Ultimately, Dr. Yealland is not Dr. Rivers’ mirror, but his foil. As the psychologist’s friend Henry Head notes, Dr. Rivers is a compassionate, dedicated man and not at all like the sadistic Dr. Yealland. According to Head, Yealland's lack of humanity helps to better highlight Dr. Rivers’s own essential kindness. Dr. Rivers goes beyond his duty to ensure his patients’ well-being. While on sick leave, he visits a former patient and stays with him for days; he remains in contact with his old patients even after moving to London. Moreover, Rivers is acutely aware of and disturbed by the pain that any kind of treatment can cause. While watching Dr. Yealland's session with Callan, Dr. Rivers identifies not with his colleague but with the patient, recalling his own painful memories of stuttering. After witnessing the scene, Rivers becomes physically ill and suffers from a nightmare. In fact, Rivers is so unsettled by Dr. Yealland that his own stutter returns. Dr. Rivers then agonizes over the effectiveness of his own treatment, worrying about the effects of emasculation and dependency. The fact that Yealland leads Rivers to question his own methods is further evidence of Rivers's compassion. Even though the psychologist may fear that he harbors similarities to Yealland, Dr. Rivers remains the novel’s moral protagonist.
Part of what makes Dr. Yealland a reprehensible doctor is his belief in his own authority. The doctor acts like a tyrant and treats his patients as sub-human. Yet Dr. Rivers rejects the easy sense of superiority that comes with being an anthropologist or a psychologist. He recounts an experience in which the native people he interviewed in the Solomon Islands showed him the power of cultural relativism. Dr. Rivers embraced the theory, acknowledging that he was not the islanders’ superior, but their equal. He brings the same humility to psychology: he does not believe himself to be better than his patients. Rivers opens himself to alternate views; he genuinely listens to Sassoon and allows himself to be changed by him. This introduces yet another irony: Dr. Rivers was tasked with changing Sassoon, but by the end of their time working together, the lieutenant actually changed the doctor. By the end of the novel, the psychologist is no longer willing to give England his unquestioned allegiance. Such a transformation would never have been possible had he insisted on his own superiority or held himself at a distance from his patients.
By the end of the novel, Sassoon has lost hope of his anti-war protest ever succeeding, realizing that his stay at Craiglockhart has effectively undercut his critique. Stopping the war was the lieutenant’s only reason for leaving the front; once this becomes impossible, his guilt forces him to return. Whatever his feelings about the war, Sassoon’s ultimate allegiance is to the men he fought with and who continue to fight. Sassoon's way of reconciling this contradiction is to die in battle - perhaps this will even prove his point. As Dr. Rivers explains, the lieutenant has lost all interest in the future. Yet Sassoon’s integrity prevents him from completely resigning himself to his fate. When questioned by the board, he defends his beliefs, refusing to pretend that his opinions about the war have changed. He is breaking - but he is not completely broken.
in Part IV, Barker continues to elaborate on the emasculation that the men at Craiglockhart are suffering, both as soldiers and as patients. Dr. Rivers ponders the effects of helplessness on people’s psyches, explaining that prolonged periods of dependence can lead to the same neuroses in men that afflict many women in times of peace. Through combat, Rivers explains, the men have become like women, whose limited socio-cultural roles leave them unable to take control of their lives. Psychology also leaves men emasculated, as Dr. Rivers’s dream graphically depicts. In his nightmare, Rivers attempts to shove something into a patient’s glistening, pink mouth; the psychologist even notes that this part of his dream is reminiscent of a rape scene. The treatment has therefore converted the patient into a helpless being, an image which, at the time, was commonly associated with women.
The novel’s ending is melancholy. Though there is some hope—Prior has found love; Sassoon and Owen have built a close friendship; Dr. Rivers has begun a wonderful new job—the tone is markedly sad. Anderson has grown more dependent. Willard is cured but still completely delusional about the nature of his injury. We know nothing of Burns after his attempt to commit suicide. Owen is left alone without the man he has grown to love. Perhaps most devastatingly of all, a depressed Sassoon is returning to war, where he will likely be killed. The sense of doom is not limited to the characters: the landscape of war keeps impinging on the home front. London, a normally bustling and well-lit city, is dark and goverened by the collective fear of air raids. Hospital corridors have become No Man’s Land. Even Dr. Rivers, who worries about Sassoon’s suicidal tendencies, fails to protect himself during the air raids, seemingly resigning himself to his fate. Though Barker gives her readers some reasons for optimism, she insists upon reminding us about the lingering darkness of war.