The image shows Williams, as the late screen icon, walking through a crowd of men as photographers trail her.
Based on two memoirs by Colin Clark, "My Week with Marilyn" tells the story of the week Clark spent showing Monroe around England while she was filming "The Prince and the Showgirl" with Sir Laurence Olivier in 1956.
The film stars Eddie Redmayne as Clark, Kenneth Branagh as Olivier and Dougray Scott as Monroe's new husband, playwright Arthur Miller. Judi Dench, Dominic Cooper and Emma Watson also star.
"My Week with Marilyn" will arrive in theaters on Nov. 4, after premiering at the New York Film Festival in October.
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