It is through this opportunity that the novelist reveals the extent to which Nurse Ratchet actually dominates the rest of the staff as much as she dominates the daily lives of the patients. In some ways, she represents the hypocrisy of mental institutions, especially in that day and age. Specifically, the outward appearance of the institution and of all of its employees (including the nurses) is perfectly clean and sanitary and (as represented by the white uniforms), innocence. Nurse Ratched, in particular, is polite and proper to a fault and obviously masking the true dark nature of her character. In reality, Ratchet is cold-hearted person who deliberately enforces arbitrary decisions and rules even though she has the authority to make relatively meaningless and harmless adjustments that would improve the daily life and circumstances of her patients.
Initially, McMurphy takes everything that happens somewhat lightly and he is a constant source of humor to Chief, in particular. However, the humorous tone vanishes when...
She purposely shames him sexually and threatens to tell his mother about the sexual liaison with McMurphy's female friend. When Billy commits suicide because of it, McMurphy attacks Nurse Ratched and nearly strangles her to death. Largely because of that, McMurphy is lobotomized, leaving him as what Chief has always described as a "vegetable." The contrast between the McMurphy that Chief knew before and the vegetable he has been turned into is too much for Chief and he kills McMurphy with his bare hands to put him out of his misery and prevent him from having to live the rest of his natural life in a condition he knows McMurphy would not have wanted to live. Ultimately, this act frees both McMurphy in the spiritual sense and Chief, who escapes from the institution because of the situation.
