Some people passing by newsstands might think that Vogue decided to go all retro for their October cover and publish a photo of Marilyn Monroe. They’d be wrong. Sort of.

Courtesy of Vogue

It’s actually Michelle Williams channeling the icon, whom she plays in “My Week With Marilyn,” which debuts next month at the Tribeca Film Festival. The movie chronicles Monroe’s turbulent experience filming the 1957 film “The Princess and the Showgirl” opposite Sir Lawrence Olivier. It’s loosely based on two books by Colin Clark, who was an assistant on the set of the movie and spent time shepherding the icon around England after her then-husband Arthur Miller had left the country.

To prepare to play the icon, the 31-year-old actress tells Vogue that she immersed herself in all things Marilyn for six months. “I’d go to bed every night with a stack of books next to me,” Williams says in the cover story. “And I’d fall asleep to movies of her. It was like when you were a kid and you’d put a book under your pillow hoping you’d get it by osmosis.”

Learning to prepare for the role mentally was one thing. The physical transformation was something else. Williams tells Vogue that when she tried to gain weight to mimic the bombshell’s curves, “it went right to my face … So at some point it became a question of, Do I want my face to look like Marilyn Monroe’s or my hips?”

From the cover, it’s clear what she chose.

For more from the article, head to Vogue.com