Hayden Panettiere did it last month (click here to see it) and, now, Michelle Williams has chopped off her long locks. (Check out other dramatic celeb hair makeovers here.)

The actress, who's at the Cannes Film Festival to promote her upcoming movie, "Blue Valentine," opposite yummy Ryan Gosling, revealed her new platinum pixie cut during a photo op on Monday.

(See other celebs who have gotten super-short crops here.)

Do you think the new look (C) is flattering? Or do you prefer the longer locks she wore at the Berlin Film Festival in March (B) or maybe the bob she sported at Cannes in 2008 (A)?

It's amazing what a difference hair length and color can make. Behold these eye-catching celeb transformations.

Get more beauty scoop and photos of celebrity hairstyles.

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