England 1956. Bucking the trend of his highly successful academic and aristocratic family, twenty-three year old Colin Clark (Eddie Redmayne) is instead determined to work on the production side of movies. Having met him previously, Colin doggedly pursues a job, any job, with Laurence Olivier Productions. Because the company will soon be filming a movie titled "The Sleeping Prince" (which will eventually become The Prince and the Showgirl (1957)), Colin eventually gets a job as an unpaid assistant, which morphs into a paid job as Third Assistant Director for the lighthearted comedy, which is to star Sir Laurence Olivier (Sir Kenneth Branagh) and Marilyn Monroe (Michelle Williams), whose entourage includes her husband, playwright Arthur Miller (Dougray Scott), and one of her Method acting coaches, Paula Strasberg (Zoë Wanamaker), and be directed by Olivier. Colin sees that Monroe is a very scared and insecure person about her acting abilities, and thus paranoid, she who requires the constant support of her entourage, especially Miller and Strasberg. These insecurities lead to problems on the set with almost all of the others, which is exacerbated by Olivier's angry frustration toward her, he who does not believe in the Method. It does not help that Olivier's wife, Vivien Leigh (Julia Ormond) has her own insecurities about what she believes is Olivier's romantic fascination with Monroe. Seeing the problems, Colin tries to bolster Marilyn's confidence with his own secret words of encouragement. So when Miller decides to head back to the U.S. early, leaving a fragile Marilyn to feel abandoned, she searches for another source of support which she believes she has found in Colin. Colin's ensuing time with Marilyn during production threatens many things in his life, including his burgeoning romantic relationship with the production's wardrobe assistant, Lucy (Emma Watson). Through the process, Colin may be in way over his head, as most people who see him and Marilyn together suspect he is.