Nurse Ratched’s next play against McMurphy starts the day after the fishing trip. She posts a “statement of the patient’s financial doings over the last few months,” something that must have required hours of work. Everyone, except McMurphy, had a decline in funds. While McMurphy is on a long distance phone call, Nurse Ratched begins a group meeting without him and discusses McMurphy’s winnings. She implies that he’s only acting out of selfish gain. In his time he has accrued $300. Some of the men seem slightly swayed by the logic of her argument, but later Harding says that McMurphy has always made it very clear that he’s a con-man, and if anything they’ve gotten their money’s worth.
Ratched keeps trying to find an angle that will make the men turn on McMurphy, and while this one makes them a little dubious, it ultimately doesn’t succeed. Once again, the point isn't that McMurphy isn't a cheater and a con-man. He is! But he's honest about it. He told the men he was a con-man, and sometimes he cons them. But in the process he helps to make them men.
Bromden says he never felt suspicious about McMurphy until an event with the control panel. McMurphy wants to see if his training regimen has worked for Bromden, and asks if he can lift the control panel to see if any progress has been made. Bromden can move it nearly half a foot. McMurphy tells him to keep this a secret. The next day McMurphy makes another bet with the patients about moving the control panel. When Bromden reluctantly lifts it, and McMurphy wins. He tries to give Bromden five dollars for gum money, but Bromden refuses it thinking McMurphy is perhaps just using him. When McMurphy asks why the men are suddenly treating him like some kind of traitor, Bromden says it’s because he’s always winning.
Bromden doubts McMurphy’s motives after he lies to the men that he knew Bromden could lift the control panel, and takes money from the bet. Bromden refuses the money on principle, thinking perhaps he has been duped this whole time. McMurphy is far from always winning, though. While he may have been successful in some bets on the ward, on a grand scale his life is in jeopardy with him pitted against Nurse Ratched.
Nurse Ratched ensures that everyone who went on the fishing trip has to get a mandatory shower, “a cautionary cleansing” in light of the company they’d kept, and in hopes nothing would spread throughout the hospital. George Sorenson has a phobia of cleanliness and he begs them not to spray him with their putrid salve. McMurphy loses his temper and gets into a fistfight with the aides, and Bromden joins in on the fight. At the fight’s end, all of the patients are congratulating McMurphy on a good fight, but Nurse Ratched has both McMurphy and Bromden sent to Disturbed. McMurphy enters Disturbed introducing himself like he had at the ward over a month before, asking where the gambling boss is on this floor. A Japanese nurse, who is nice to them, explains that nurses who were in the Army, like Nurse Ratched, tend to try to run things like they’re still in an army hospital. She says they’re “a little sick themselves,” and that she sometimes thinks “all single nurses should be fired after they reach thirty-five.”
McMurphy finally snaps at the inhumane treatment of George Sorenson and starts a fight with the aides. McMurphy's action dismisses any of Bromden's concerns about being deceived, because McMurphy wouldn’t step in for George if he didn’t really care about the men. It’s clear the other men agree when they clap for McMurphy at the end of the fight. McMurphy approaches the entry to Disturbed like he did the other ward, searching for the boss, but knowing he’s not going to find one here. The Japanese nurse on Disturbed is a refreshing voice of clarity against Nurse Ratched’s vicious ways. She confirms that Nurse Ratched’s methods are cruel and emasculating, linked to her being “single” and “over thirty-five” (which, it must be mentioned, is a rather stereotypical view to take of an "old maid")
Bromden and McMurphy are assigned beds next to each other, but Bromden isn’t tied down. He is woken in the middle of the night by a patient who is yelling, “I’m starting to spin, Indian! Look me, look me!” The man’s hungry, yellow-toothed face haunts Bromden, and he wonders how McMurphy can possibly sleep when he must be “plagued by a hundred faces like that, or two hundred, or a thousand,” all desperate for his attention.
Bromden cannot comprehend how McMurphy can sleep when he’s surely haunted by so many more faces than Bromden, because McMurphy is carrying the weight of so many men’s freedom and dignity on his shoulders.
Nurse Ratched visits Disturbed the next day and says that the patients agreed with the staff that it might help McMurphy to receive shock therapy unless he admits that he was in the wrong and demonstrates it through obedience. McMurphy refuses, saying she should add some other things for him to sign on to like saying living in her ward is like living in Hawaii, and that “those Chinese Commies could have learned a few things from you, lady.” McMurphy and Bromden are sent to the Shock Shop. McMurphy doesn’t seem afraid, so Bromden resolves not to yell or cry.
McMurphy refuses to admit he did anything wrong because he sticks to his principles, and refuses to let Nurse Ratched win. He compares her to the Communists in China because she is so inhumane, but also because he knows she was an army nurse and that it will anger her. McMurphy approaches shock therapy like a martyr, and acts unafraid because he cannot allow himself to be afraid because of his leadership position with the men. If he breaks, they break, and he knows it.
McMurphy gets onto the cross-shaped table without help, and asks if he’ll receive a complimentary “crown of thorns.” Bromden watches McMurphy receive treatment, and out of instinct tries to escape and struggles against the aides trying to pin him down. During his own shock treatment, Bromden is inundated with childhood memories. When he wakes up, he is able to fight off the fog for the first time after having received shock therapy, and he knows that “this time [he] had them beat.”
The table is even cross-shaped, so it’s no surprise McMurphy asks for a crown of thorns—referencing Christ at the crucifixion—because he feels he’s been persecuted and now he’s being sacrificed in the name of mental health and control. This reference also forebodes how McMurphy's self-sacrifice will free the men. Bromden comes out of his shock treatment faster than ever and realizes that he has control over his mind again, and the ward doesn’t have him anymore.
McMurphy gets three more shock treatments that week alone. As soon as the old spark in him would return, Nurse Ratched would come up and order another round. Bromden tries to talk McMurphy into playing along so they’ll stop the treatments, but McMurphy jokes that they’re just recharging his battery for free and the first woman he’s with after this will “light up like a pinball machine and pay off in silver dollars!” He claims he’s not scared of “their little battery charger.” Bromden can tell, though, that the treatments are affecting McMurphy because he looks unusually pained, pale, “thin and scared,” whenever he’s called in for another. Bromden is sent back to the ward under Nurse Ratched’s control, and he tells the patients even better stories about how McMurphy is completely resistant to the treatments than they’ve already heard through the rumor mill. Nurse Ratched realizes, though, that McMurphy is only becoming more a hero now that the men can’t see him actually failing under the shock treatment, and so she brings him back from Disturbed.
McMurphy keeps refusing to say he was in the wrong; he knows the men on the ward need him to be a symbol of strength against the authority of the institution. Nurse Ratched moves him back down because she sees how McMurphy has grown to the mythic status he hoped to. She believes she can crack him and them by showing he is just a man after all.
Knowing that Nurse Ratched will only keep hounding McMurphy, many of the patients tell him he should make a break for it. McMurphy responds, though, that tonight is the night of Billy Bibbit’s date with Candy Starr and he can’t leave yet because it would disappoint Billy. In a group meeting that day, Nurse Ratched suggests that McMurphy consider an operation, saying that there’s “no cutting” involved. McMurphy says there’s no use in lopping them off, he’s “got another pair in [his] nightstand.” Nurse Ratched looks furious when she realizes McMurphy’s entendre.
McMurphy knows he can escape, but he won’t leave because escaping would be the same as giving in. It's not just his life that's important. It's all the patient's lives. In the meeting, McMurphy uses sexual language to unsettle Nurse Ratched again, with success, insinuating he has another pair of balls so she can take away the ones he has.
The men are in high spirits after the meeting as they look forward to the party in the ward that night. At midnight, when Geever and the other aides besides Mr. Turkle go off duty, McMurphy gets Mr. Turkle to let Candy in through the window and to unlock the Seclusion Room for Billy Bibbit and Candy. Candy arrives later on with Sandy, bringing loads of alcohol. Everyone starts mixing their drinks with cough syrup, while McMurphy and Turkle smoke weed. Sefelt has a seizure next to Sandy, and she watches him “with quiet awe.” Fredrickson puts a wallet between Sefelt’s teeth. Sefelt grins when he comes out of it and asks for medication. Harding goes to the drug room, which has been unlocked, and sprinkles “a double handful of pill” over Sefelt and Candy. Harding makes a long speech about how “It is our last fling. We are doomed henceforth. Must screw our courage to the sticking point and face up to our impending fate. We shall be all of us shot at dawn.” Billy and Candy go to the Seclusion Room after four a.m.
Sefelt takes his medicine at the party, something he previously refused to do, because he feels a new kind of freedom where he knows that he can live in the outside world, experience these seizures, and use the medicine to his benefit. Harding, though, makes a doomsday speech because he knows that the next morning everyone will get in huge trouble for the party. He hopes that McMurphy can escape, but he feels that realistically it won’t happen.
As morning approaches, Harding becomes adamant that McMurphy’s must now escape and that they must do something about the mess on the ward. He says they should tie up Turkle so it looks like the party mess was a byproduct of McMurphy’s escape, that way Turkle won’t lose his job and the other patients will avoid getting in trouble. McMurphy can drive off with Candy and Sandy to Canada or Mexico. When McMurphy asks if anyone else wants to come with him, Harding says he’s nearly ready to go, but he wants to do it with all the red tape. Bromden says he doesn’t know where he wants to go yet. Harding promises McMurphy that the rest of the patients are “still sick men in lots of ways. But at least there’s that: they are sick men now. No more rabbits, Mack.”
Harding concocts an entire plan that would absolve the rest of the patients from punishment while McMurphy escapes. The others won’t escape now because they still aren’t ready, but they are men now, and that’s what’s important. Harding is trying to tell McMurphy that his work is done. McMurphy's failure to take his advice suggests that McMurphy, who has more experience than Harding, doesn't quite agree.
McMurphy gets into bed with Sandy and asks Turkle to wake them up before the morning staff gets to the ward. Turkle falls asleep, though, and the aides discover everyone. Bromden says that what happens next was inevitable, whether McMurphy had escaped or not. Even if McMurphy had managed to get out, he wouldn’t bear to be away to “let the Big Nurse have the last move and get the last play…It was like he’d signed on for a whole game and there wasn’t any way of him breaking his contract.”
Bromden’s admission that the following events were inevitable show McMurphy’s dedication and love for the men: he couldn’t bear to know Nurse Ratched would come out victorious, even at the expense of his own freedom—or his life.
As the patients on the ward wake up, they are amazed at the party they had the night before. As Nurse Ratched discovers more and more damning evidence, the patients start laughing uncontrollably, which only makes Nurse Ratched angrier. Turkle opens up the screen on the window to let Sandy out, and McMurphy has the opportunity to escape with her, but he refuses even though Harding begs him to go, saying he’s done his best to warn him—“predicting doom.” An aide notices the unlocked window and locks it back up.
McMurphy has the opportunity to escape, but he doesn’t because he can’t leave his men behind; he feels responsible.
Nurse Ratched discovers Billy and Candy in the Seclusion Room and is shocked and appalled, though Billy appears happy. Everyone on the ward has crowded around and laughs when they see Billy and Candy together on the mattress. However, when Nurse Ratched threatens to tell Billy’s mother about what he’s done, he falls into hysterics. He starts stuttering, crying, and begging her to not say anything to his mother and then he begins to blame Candy, McMurphy, and Harding, saying that they all forced him to have sex. Nurse Ratched sends Billy to Dr. Spivey’s office to cool off and think while she deals with the rest of the patients. But once in the office, Billy slits his throat, killing himself.
Billy is initially happy and proud when woken up, but when his mother is used as a threat against him this drives him to kill himself because he can’t bear to think of his mother’s judgment or the judgment of others in and outside of the hospital. He was not yet strong enough to face Ratched's use of shame against him.
Nurse Ratched approaches McMurphy with the news of Billy’s death and asks him if he’s satisfied with how he’s gambled with human lives like Billy and Charles Cheswick. She accuses McMurphy of playing God. She heads back to the nurse’s station. Bromden watches McMurphy and says he knows that there is nothing that could have stopped him from what he was about to do: it wasn’t the nurse forcing him, “it was us that had been making him go on for weeks, keeping him standing long after his feet and legs had given out” because of the shock treatment. McMurphy punches through the glass at the nurse’s station and takes hold of Nurse Ratched, ripping open the front of her uniform, exposing one of her breasts, while he tries to strangle her. When McMurphy is pulled off of Nurse Ratched, he cried out “a sound of cornered-animal fear and hate and surrender and defiance.” Bromden compares it to the final sound an animal makes before the dogs close in on it, “when he finally doesn’t care any more about anything but himself and his dying.”
Nurse Ratched blames McMurphy for Cheswick and Billy’s deaths. And she really does seem to think it's his fault. She thinks that it was the way he helped them not to conform, rather than her shame-based demands for conformity, that killed them. Bromden knows there’s no stopping McMurphy from what he’s going to do when he attacks Nurse Ratched and tries to strangle her. When he rips the front of her uniform, this serves as a symbol of masculine dominance over the feminine. Ratched is revealed to be a “she” who is helpless against McMurphy’s grip. Her womanhood now makes her subservient in this assault. McMurphy’s cry when he’s tackled is one of resignation, he knows that he’s signed his own death warrant, and death is all he wants.
In the week after McMurphy attacked Nurse Ratched, while Ratched is on medical leave, Sefelt and Fredrickson signed out of the hospital Against Medical Advice, and then three more Acutes left while six transferred to a different ward. Dr. Spivey is asked to resign but refuses. For the week that Nurse Ratched is away, the ward has the nice Japanese nurse, and the men still on the ward change a lot of policy: the tub room is restored to the blackjack room and Harding took over the role of dealer. When Nurse Ratched returns, everyone approaches her in the hall to ask about McMurphy. She looks beat up, and flinches at their approach. Her new uniform doesn’t conceal the shape and size of her breasts. Nurse Ratched says that McMurphy will be back.
The ward changes after the attack. Nurse Ratched’s power, now that McMurphy's attack revealed her not as an implacable force but a woman wearing a uniform who could be physically cowed, has mostly dissolved and patients are checking out and leaving because they feel like men now, independent and capable. When Ratched returns, her new uniform doesn’t conceal the shape of her breasts, which serves as a symbol of how McMurphy and the men succeeded in subverting her non-sexual matriarchal power. The men regained control of the ward and themselves.
Nurse Ratched tries after that to return the ward to the way it was before McMurphy, but his noticeable absence keeps the ward alive with men laughing in meetings and singing in the showers. Patients keep signing themselves out of the ward, and then Harding signed out and was picked up by his wife. George Sorenson transferred. After a few weeks, only three of the fishing crew were left: Bromden, Martini, and Scanlon
One day, McMurphy is wheeled back into the ward on a gurney with a chart reading “Lobotomy.” The men don’t believe that it’s him at first; he’s a complete vegetable. Bromden was sure that McMurphy would never have his name attached to a body stored like that in the day room for the next twenty or thirty years just so Nurse Ratched could use him as “an example of what can happen if you buck the system.” That night, Bromden suffocates McMurphy with a pillow and remarks that he looks the same in death as he did after the lobotomy.
McMurphy was lobotomized, and the men can’t recognize him because this isn’t McMurphy— this is the shell of a person. Ratched, effectively, had him killed. Bromden knows that she did this so he would be a half-living example of what happens when you go against her, and McMurphy would never want that. Bromden's suffocation of McMurphy is therefore an act of mercy.
Following Scanlon’s advice that he should run, Bromden lifts the control panel and throws it through the window. He can hear aides running down the hall, so he jumps out of the window and runs across the grounds in the direction he recalls seeing the stray dog run. He knows no one will come after him, and that Scanlon could handle any questions about “the dead man,” but he keeps running until he reaches the highway, where he hitches a ride with a Mexican trucker. Bromden says maybe he’ll go to Canada one day, but he’d like to stop in Columbia and Portland, Hood River, and The Dalles to see if any of the people he used to know are still around and sober. He’s heard that some of the Indians have taken to building a wooden scaffold over the government’s hydroelectric dam and spearing salmon, and he’d like to see that. But mainly he wants to just see the land again. He says he’s “been away a long time.”
Bromden throwing the control panel out shows the progress of the men in the book. The control panel—a symbol of the mechanized ward and the machine-like Combine—was once impossible to lift, like the wolf was once impossible to fight. Now Bromden has thrown it out of the window and escaped the ward and is finally free. He follows the path of the stray dog he saw that one night, because in many ways Bromden is stray, he has returned to his natural state of man—he’s animalistic. His urge to return home and see familiar things—and to see how some of his Native American kin have founds ways around the Combine-created hydroelectric dam men have—is a desire to reconnect to both his past before the Combine and his future figuring out ways around the Combine. His final line is true both literally and figuratively: he’s been away from home and he’s been mentally absent.