Michelle Williams' Risque Corset Dress: Yay Or Nay? (PHOTOS, POLL)

Michelle Williams, a perennial fan of floral dresses and peplums, usually sticks to a pretty tame style palette.

But all Peter Pan collars were off at Thursday night's "Take This Waltz" screening, where Michelle ditched her girlie duds (at least until Friday morning) for a seriously sexed-up look.

In a sexy lace-up Altuzarra dress and strappy white Givenchy heels, Williams bared a hint of cleavage as she promoted her new movie alongside co-star Luke Kirby. In the movie, Williams and Seth Rogen play a married couple whose relationship is tested by an attractive new neighbor. (Kirby, obvi -- look at him!) Boyfriend Jason Segel, unfortunately, was nowhere in sight.

Speaking of attractive folks in Hollywood... Michelle's not looking too bad herself.

Check out Williams' new look below!

michelle williams

michelle williams

Michelle Williams' Style Evolution

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