Ratched is just a nurse trying to do her job as well as she knows how; McMurphy, a racist and statutory rapist, insists on causing mayhem on her ward.
McMurphy himself, who is diagnosed in the play with a pathological need to flout authority and be the center of attention... Which seems about right.
Complete Monster: Ratched, the "Big Nurse", is the cruel head of the state hospital the story takes place in, using her connections to her superiors to allow herself free reign over the hospital. Ratched subjects her dozens of patients to horrific conditions and abuse, employing brutal lackeys and methods to keep patients in line and under her thumb, uncaring of the countless patients who commit suicide or self-mutilation due to her rule. Believing that her patients have to be perfectly-functioning before allowing them to leave, Ratched often resorts to electroshock treatments and even lobotomies to destroy her patients' minds. When her rule is challenged over and over again by Randle McMurphy, Ratched increases her abuse of the patients to the point that one of McMurphy's friends kills himself. Though Ratched's control over the patients is broken, she spitefully has McMurphy lobotomized in a last-ditch effort to terrorize the patients into falling back in line.
Hilarious in Hindsight: Big Nurse Ratched's name has taken on a funny quality now that "ratchet" has become teen slang used to describe anything with the quality of the ghetto about it.
Ho Yay: Plenty in the novel, but not between any specific characters and used more to build up the discomforting, emasculating atmosphere of the hospital than to establish the sweetly ambiguous kinds of relationships that the trope is associated with.
There's some between Chief and McMurphy
Chief: That's a lie. I know hes still alive. That aint the reason I want to touch him.I want to touch him because hes a man.Thats a lie too. Theres other men around. I could touch them. I want to touch him because Im one of these queers!But thats a lie too. Thats one fear hiding behind another. If I was one of these queers Id want to do other things with him. I just want to touch him because hes who he is.
And then there are the orderlies. According to Bromden, they love to give patients showers. They always check the patient's temperature at the same time they shower the patient, and they go down to Miss Ratched beforehand to get a rectal thermometer and a bottle of Vaseline. She admonishes them to use the minimum amount of Vaseline necessary, but they take the whole bottle inside with them, and they turn up the water pressure till the noise makes it impossible to hear anything that's going on inside...
Moral Event Horizon: Nurse Ratched has been on the wrong end of the moral event horizon for many years, as she is seen to submit her charges to torture for crossing her (the scene with the germophobe after the fishing trip, the forced anal administration of medication to a patient merely because he questioned what the pills were for), the electroshock 'therapy', and she has also lobotomized patients as punishment for behavior she dislikes. Nurse Ratched is utterly monstrous in the book.
Of course, given the book's expert use of Unreliable Narrator, it's hard to tell if she really is that bad or if it's the Chief projecting onto her. Remember, he also thinks that the orderlies are evil robots.
The African-American orderlies are treated a bit indelicately, and McMurphy even drops an N-Bomb. In the book, the orderlies are overtly thugs and rapists.
Many people find the book to be misogynist, what with and the idea that matriarchy is akin to castration, and the implication that no woman could/should dominate a "real man." Prostitution and McMurphy's statutory rape charge are treated pretty casually. Ratched's violent comeuppance is, in the book, very sexualized and supposed to be seen as a moment of dishing out truly justified retibution.
McMurphy's charge of statutory rape—in the time the book was written, it wasn't as serious a crime. McMurphy also alleges she told him she was eighteen, and he wasn't found guilty of it, but he does brag about it. The book and movie asks you to see him as an admirable anti-authority figure.
The Woobie: Every character that's not Nurse Ratched or McMurphy at least until the end. Charlie Cheswick and Billy Bibbit come to mind especially, however.
Alternative Character Interpretation: Nurse Ratched may not be a very nice person, but she's just trying to do her job as well as she knows how. McMurphy is really a Decoy Protagonist while the movie was really about Chief Bromden finding the courage to escape from the mental institution.
Award Snub: Not that it went home empty-handed. But many still believe Brad Dourif was robbed for his role as Billy Bibbit.
Ho Yay: In the film, there's Billy/McMurphy. McMurphy even says to Candy something like, "I just want you to do this one thing for me. He's cute, isn't he?"
In the film, much of Sefelt and Fredrickson's interactions-such as their inseparability, how Fredrickson is always touching the older man, them dancing together at the party, and them passing out with their beds pushed together afterwards- can be seen as this
Moral Event Horizon: Nurse Ratched might just be a mean and misguided nurse trying to do her job, right up until the point where she threatens to tell Billy's mother about his "bad behavior", knowing full well the trauma that would cause him, which leads to his suicide.