Miloš Forman's 1975 adaptation of Ken Kesey's One Flew Over the Cuckoo's Nest is recognized as one of the finest motion pictures ever assembled. The film earned critical plaudits across the board and is currently ranked #18 on IMDB's Top 250 with an 8.7/10 rating. The film also holds a 93% Certified Fresh Rotten Tomatoes rating and an 83/100 Metascore.

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The story follows Randle McMurphy (Jack Nicholson), a small-time criminal who pleads insanity to avoid jail time. When he's interned at a mental institution, the independent spirit fosters rebellious change among his fellow inmates. One Flew Over the Cuckoo's Nest won all five major Oscar Awards, including Best Picture, Director, Actor, Actress, and Adapted Screenplay.

It Was Produced By Michael Douglas

Michael Douglas on set

One Flew Over The Cuckoo's Nest was first adapted to the stage in 1963 and starred Kirk Douglas in the role of McMurphy. Douglas bought the film rights to the novel when he read the story in galley form in 1961, and had plans to reprise his starring role on the big screen.

However, development took far too long and Douglas became too old to take up the role. Douglas then gave the rights to his son, Michael Douglas, to produce with Miloš Forman set to direct after Hal Ashby was initially considered. This turned out to be a wise decision, as Michael Douglas won a Best Picture Oscar for producing.

It Was Filmed In A Real Mental Hospital

One Flew Over The Cuckoo's Nest was filmed at a real-life functioning mental hospital in Salem, Oregon. Several of the extras and background performers were real patients. Forman even spent a month living in the Oregon State Mental Hospital to observe the environment prior to filming and would roll cameras without anyone's knowledge.

Oregon State Mental Hospital was chosen because superintendent Dr. Dean R. Brocks permitted unlimited access to the facility, including the presence of real doctors. At one point during production, a crew-member left a second-story window open to relay cables, resulting in a patient wriggling through the bars, falling to the ground, and injuring himself.

Jack Nicholson Delayed Production When He Was Cast As McMurphy

Randle in One-Flew-Over-The-Cuckoos-Nest

Ken Kesey was highly critical when Jack Nicholson was cast as McMurphy since he felt that the actor just didn't fit the role. What some may not know is that Nicholson was suggested not by Forman but the initial director, Hal Ashby. This would mark a major first in Nicholson's career, since he never played this kind of character before.

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Before Nicholson was cast, the role was offered to James Caan, but he turned it down. Others considered for the leading role included Burt Reynolds, Steve McQueen, Marlon Brando, and Gene Hackman. When Nicholson won the role, production was delayed for six months to accommodate his schedule, allowing Douglas to arrange the perfect ensemble.

Nurse Ratched Was A Highly Sought-Out Role At The Time

Nurse Ratched in One-Flew-Over-The-Cuckoos-Nest

Nurse Ratched was one of the most sought-after parts in Hollywood at the time the film was in production. Although Louise Fletcher ultimately won the role just a week before filming, she auditioned multiple times over a six-month span to get it. Other actresses up for the role included Anne Bancroft, Angela Lansbury, Geraldine Paige, Ellen Burstyn, Faye Dunaway, Jane Fonda, Audrey Hepburn, Jeanne Moreau, and Shirley MacLaine.

Fletcher, who gave the character the first name Mildred in the film (she was unnamed in the novel) and is the farthest thing from the sadistic nurse seen in the film, found the role so disturbing that she refused to watch One Flew Over The Cuckoo's Nest even years after it was released.

Jack Nicholson & Milos Forman Had A Heated Falling Out

Nicholson Director

While author Ken Kesey was upset with the entire production, friction also began to mount between Forman and star Jack Nicholson during filming. The feud had much to do with the motives of McMurphy as a character and how he should be portrayed. One major disagreement sparked when Nicholson arrived on set with a thick bushy beard that he found appropriate for the part, which Forman didn't agree with.

The tension escalated so much that the star and director began communicating through the cinematographer, Bill Butler. The animosity was so strong that Nicholson even refused to partake in the film's DVD bonus material, which was released decades after the film's completion.

There Were A Total Of 3 Cinematographers

Chief and Randle in One-Flew-Over-The-Cuckoos-Nest

Two-time Oscar-winning cinematographer Haskell Wexler worked on the film for 30 days before being replaced by Bill Butler. Wexler claimed he was fired for concurrently making Underground, a documentary about a radical terrorist group The Weather Underground Organization (WUO).

Bill Butler also worked on the film for 30 days before leaving to serve another project. Butler's absence gave William A. Fraker the opportunity to step in and film the boat scene.

The Fishing Scene Was A Nightmare To Film

Fishing trip in One-Flew-Over-The-Cuckoos-Nest

Speaking of the boat and fishing trip, it was the scene last to be filmed. The rest of the movie had been shot in sequence. Initially, Forman did not want the fishing scene, as he felt keeping the story enclosed in the mental ward would be more dramatic. He did eventually get around to filming it, but not without great cost.

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Other than Nicholson, the entire cast got seasick while filming the fishing sequence. Worse yet, the entire sequence took a full week to complete to Forman's liking. To this day, Danny DeVito continues to have nightmares about making this part of the movie.

 Sydney Lassick's Meltdown Was Real

Call it a case of cabin fever or life imitating art, but actor Sydney Lassick (who plays Cheswick) suffered a serious psychological meltdown while making One Flew Over The Cuckoo's Nest. His behavior on set became continually erratic to the point that the cast and crew were concerned for his well-being.

Lassick's condition culminated in an emotional breakdown during the climactic scene between McMurphy and Chief. In the end, Lassick burst out into tears and had to be physically removed from the set.

William Redfield Found Out About His Leukemia On Set

Harding in One-Flew-Over-The-Cuckoos-Nest

As part of the all-encompassing collaboration, real doctors were on set during filming. On hand was the aforementioned hospital superintendent and psychiatrist, Dr. Dean R. Brooks.

During production, Dr. Brooks noticed something amiss with actor William Redfield, who plays Harding (above, far left). Upon examination, Dr. Brooks rightly diagnosed Redfield with leukemia, which ultimately claimed Redfield's life 18 months later.

The Author Really Hates The Movie

Ken Kesey

Ken Kesey, who based his novel on his time working as a volunteer in a mental health facility based in California, was incredibly displeased with how the film supposedly destroyed his vision due to the number of drastic changes it took. One of his biggest issues was how the movie focused on McMurphy, when the book was told from Chief's perspective. As a result, Kesey sued the producers.

Kesey wanted five percent of the movie's grosses and $800,000 in punitive damages, ultimately agreeing on a settlement. Kesey claims to have never seen the film in its entirety, only once seeing it randomly on cable TV before switching the channel when he realized what movie it was.

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