structural:summarization
1954–1955: Conflicts with 20th Century-Fox and marriage to Joe DiMaggio

Monroe had become one of 20th Century-Fox's biggest stars, but her contract had not changed since 1950, so that she was paid far less than other stars of her stature and could not choose her projects. Her attempts to appear in films that would not focus on her as a pin-up had been thwarted by the studio head executive, Darryl F. Zanuck, who had a strong personal dislike of her and did not think she would earn the studio as much revenue in other types of roles. Under pressure from the studio's owner, Spyros Skouras, Zanuck had also decided that Fox should focus exclusively on entertainment to maximize profits and canceled the production of any "serious films". In January 1954, he suspended Monroe when she refused to begin shooting yet another musical comedy, The Girl in Pink Tights. This was front-page news, and Monroe immediately took action to counter negative publicity. At the 11th Golden Globe Awards in 1954, Monroe was named " World Film Favorite ", despite not being present at the awards ceremony.

Monroe met baseball player Joe DiMaggio in 1952, while on a blind date in Los Angeles. After two years of dating, she and DiMaggio were married at the San Francisco City Hall on January 14, 1954. They spent their honeymoon outside Idyllwild, California, in the mountain lodge of Monroe's lawyer Lloyd Wright. On January 29, 1954, fifteen days later, they flew to Japan, combining a "honeymoon" with his commitment to his former San Francisco Seals coach Lefty O'Doul, to help train Japanese baseball teams. From Tokyo, she traveled with Jean O'Doul, Lefty's wife, to Korea, where she participated in a USO show, singing for over 60,000 U.S. Marines over a four-day period. After returning to the U.S., she was awarded Photoplay ' s "Most Popular Female Star" prize. Monroe settled with Fox in March, with the promise of a new contract, a bonus of $100,000, and a starring role in the film adaptation of the Broadway success The Seven Year Itch.

In April 1954, Otto Preminger 's western River of No Return, the last film that Monroe had filmed prior to the suspension, was released. She called it a " Z-grade cowboy movie in which the acting finished second to the scenery and the CinemaScope process", but it was popular with audiences. The first film she made after the suspension was the musical There's No Business Like Show Business, which she strongly disliked but the studio required her to do for dropping The Girl in Pink Tights. It was unsuccessful upon its release in late 1954, with Monroe's performance considered vulgar by many critics.

In September 1954, Monroe began filming Billy Wilder 's comedy The Seven Year Itch, starring opposite Tom Ewell as a woman who becomes the object of her married neighbor's sexual fantasies. Although the film was shot in Hollywood, the studio decided to generate advance publicity by staging the filming of a scene in which Monroe is standing on a subway grate with the air blowing up the skirt of her white dress on Lexington Avenue in Manhattan. The shoot lasted for several hours and attracted nearly 2,000 spectators. The "subway grate scene" became one of Monroe's most famous, and The Seven Year Itch became one of the biggest commercial successes of the year after its release in June 1955.

The publicity stunt placed Monroe on international front pages, and it also marked the end of her marriage to DiMaggio, who was infuriated by it. The union had been troubled from the start by his jealousy and controlling attitude; he was also physically abusive. After returning from NYC to Hollywood in October 1954, Monroe filed for divorce, after only nine months of marriage. DiMaggio was devastated, and wrote letters to Monroe apologizing and confessing his undying love for her. Monroe was also incredibly sad, and could be seen crying in court during the divorce procedures.

After filming for The Seven Year Itch wrapped up in November 1954, Monroe left Hollywood for the East Coast, where she and photographer Milton Greene founded their own production company, Marilyn Monroe Productions (MMP)—an action that has later been called "instrumental" in the collapse of the studio system. Monroe stated that she was "tired of the same old sex roles" and asserted that she was no longer under contract to Fox, as it had not fulfilled its duties, such as paying her the promised bonus. This began a year-long legal battle between her and Fox in January 1955. The press largely ridiculed Monroe, and she was parodied in the Broadway play Will Success Spoil Rock Hunter? (1955), in which her lookalike Jayne Mansfield played a dumb actress who starts her own production company.

After founding MMP, Monroe moved to Manhattan and spent 1955 studying acting. She took classes with Constance Collier and attended workshops on method acting at the Actors Studio, run by Lee Strasberg. She grew close to Strasberg and his wife Paula, receiving private lessons at their home due to her shyness, and soon became a family member. She replaced her old acting coach, Natasha Lytess, with Paula; the Strasbergs remained an important influence for the rest of her career. Monroe also started undergoing psychoanalysis, as Strasberg believed that an actor must confront their emotional traumas and use them in their performances.

Monroe continued her relationship with DiMaggio despite the ongoing divorce process; she was also rumored to have dated actor Marlon Brando. Monroe had met playwright Arthur Miller in 1951, after being introduced on the set of As Young as You Feel by director Elia Kazan. Though he was married to Mary Slattery, they began an affair in 1955. The affair became increasingly serious after October 1955, when Monroe's divorce was finalized and Miler separated from Slattery so he could be with Monroe. The studio urged her to end it, as Miller was being investigated by the FBI for allegations of communism and had been subpoenaed by the House Un-American Activities Committee, but Monroe refused. The relationship led to the FBI opening a file on her, as they suspected she was part of a communist group. However, the FBI never uncovered any evidence proving these claims.

By the end of the year, Monroe and Fox signed a new seven-year contract, as MMP would not be able to finance films alone, and the studio was eager to have Monroe working for them again. Fox would pay her $400,000 to make four films, and granted her the right to choose her own projects, directors and cinematographers. She would also be free to make one film with MMP per each completed film for Fox.