Michelle Williams glams it up as Marilyn Monroe

Marilyn is drawing Williams some of the best reviews of her career and has put her squarely in the running for a Best Actress Academy Award.

Michelle Williams in My Week With Marilyn, which will close the Dubai International Film Festival. Laurence Cendrowicz / The Weinstein Company

The connection between Michelle Williams's acting and her personal life is so strong that even she gets the two confused sometimes.

Making last year's Blue Valentine, which painfully and intimately depicted the collapse of a young marriage, occasionally seems so intense a memory to Williams as to be a true one.

"When I look back on my life and I sort of reflect on relationships or anything, my mind folds that one into the mix of the real relationships that I've had in my life," says the actress. "And I have to stop myself and say, 'Oh, no, you did not marry and divorce Ryan Gosling'."

While delusions of wedding Gosling are not necessarily uncommon to moviegoers, for Williams they exemplify the intensely introspective approach she takes to her work.

Going by her latest film, My Week With Marilyn, it is clear Williams has undergone a shift. After years of predominantly raw, naturalistic films such as Wendy and Lucy and Blue Valentine, in My Week With Marilyn she's glamorous and radiant. That, too, is telling of an interior change in Williams.

"One thing that I've struggled with, been interested in just as a person, a girl-slash-woman, whatever I am at 31 in this world, is being comfortable with myself," Williams says. "I've just spent a lot of time getting to know that person and getting to like that person, so I haven't wanted to lose touch with that person through lenses like hair and make-up and clothes."

Yet Marilyn, which will officially close the Dubai International Film Festival tonight in a special red-carpet screening, is drawing Williams some of the best reviews of her career and has put her squarely in the running for a Best Actress Academy Award. Williams's performance somehow manages to evoke a fully fleshed person, well beyond mere caricature. It is a layered rendering of Monroe: a public, glorious Marilyn; a private and vulnerable actress; and the song-and-dance showgirl of The Prince and the Showgirl.

The film chronicles the production of that 1957 film, which Laurence Olivier directed and co-starred in with Monroe. The two clashed: an oil and water mix of classical British theatre and American movie stardom.

"There's technically an enormous challenge, which [Williams] meets lightly, effortlessly," says Kenneth Branagh, who plays Olivier. "Then she puts that all away to one side, doesn't show off to the audience about it. She doesn't indulge in playing Marilyn, she just is. It required her to work enormously hard and then hide all the work."

In an interview over afternoon tea at a Manhattan hotel, Williams is refreshingly candid. She's dressed elegantly but simply in a black-and-white dress and wearing a short, blonde pixie haircut that she has said is a tribute to Heath Ledger, her former partner and the father of her six-year-old daughter Matilda, who liked cropped hair. He died in 2008, a few months after he and Williams separated.

In a nice touch of foreshadowing, Williams kept a poster of Monroe on her bedroom wall as a teenager. As her young acting career grew in TV and movies, she emancipated herself from her parents at age 15. Two years later, she was cast in Dawson's Creek, the teen drama that ran for six seasons and catapulted her into stardom.

Her film career took off with 2005's Brokeback Mountain. She received her first Oscar nomination (a second would come for Blue Valentine) for her performance as the rejected wife of Ledger's cowboy.

She's since drawn the interest of directors such as Martin Scorsese (Shutter Island) and Wim Wenders (Land of Plenty), but perhaps she has been most comfortable in independent films (Synecdoche, New York and I'm Not There).

She has twice worked with the filmmaker Kelly Reichardt in low-budget films notable for their realism: 2008's Wendy and Lucy, a film about a woman living in poverty with just her dog and a beat-up car, and this year's Meek's Cutoff, a gritty depiction of life on the Oregon Trail in 1845. Williams slept in her character's car for Wendy and Lucy and learnt how to drive oxen for Meek's Cutoff.

"She really likes the chance to hide and just be able to be a person," says Reichardt. "These films have sort of offered her a chance to work while just being able to blend into the world in a way that becomes probably more difficult."

Whereas she rolled out of bed for Wendy and Lucy, My Week With Marilyn required three hours of hair and make-up every morning.

"In the film, there's a sort of contrast between the American interior, psychological way of working, and the English external, theatrical way of working," says the director Simon Curtis. "But in fact, Michelle came at the character of Marilyn from both directions."

Of the less certain times, she says, biting her lip: "Some of them I would hate to bring up." The first Oscar nomination, she acknowledges, "stymied me somehow ... I felt like people were watching. I felt like there was pressure where there used to be none".

People are still watching Williams, but it doesn't seem to bother her much anymore.

"I've noticed that now, at 31, my ideas about scenes or dialogue or moments, they come faster," she says. "And I find that I'm enjoying it and that that's not hampering my work, so maybe it doesn't have to be as hard as I was making it out to be for so many years."

My Week With Marilyn will screen tonight at Dubai's Madinat Arena at 8pm

* Jake Coyle, AP