The differences between Kesey's novel and Forman's Oscar winning film are very obvious. One Flew Over the Cuckoo's Nest, written by Ken Kesey comes from the perspective of Chief throughout the entire story. The fog and machinery add that mysterious touch to the experience in a mental ward. The reader has the chance to personally experience life in a mental ward through the eyes of a patient. In the film, Forman focuses mainly on a humorous plot along with McMurphy's life of sex and gambling. In a way the film makes Chief seem like he really is dumb. While outside playing basketball, McMurphy says to Chief, "old Indian game, It's called, uh, put the ball in the hole" (Forman). Instead of portraying Chief as the wise man he is, the film makes him seem completely opposite. In a way, the film makes fun of Chief. Kesey must've been very upset over the fact that his story was not expressed the way he meant it to be.
Another reason why Kesey disapproves of Forman's film is because the characters are not who Kesey originally intended them to be. For example, the Big Nurse is a rather large and in charge woman in the novel, who is a nasty and awful person. On the other hand, in the movie, Nurse Ratched seems like she has a heart. At times she may seem a little bossy, but she does not have the huge stature and precision of a machine. "Practice has steadied and strengthened her until now she wields a sure power that extends in all directions on hair like wires so small for anybody's eye but mine, I see her sit in the centre of this web of wires like a watchful robot, tend her network with mechanical insect skill, know every second which wire runs where and just what current to send up to get the results she wants" (Kesey). Not only is Nurse Ratched's character mismatched, but McMurphy also is not a huge, red-headed farmer in the movie, like he is in Kesey's novel. When Forman takes out these characters traits, it changes the story greatly from how Kesey wanted it to be told. That is why Kesey disapproves of the movie make of his novel One Flew Over the Cuckoo's Nest.