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Allison Williams

Over the past few years, Allison Williams has volleyed between her natural medium-brown shade of brunette and various shades of blonde, looking incredible all the while. And although she apparently had intended to stay brunette, a new acting gig had other plans for her. "I swore I wouldn’t do this to my hair again ... but new movie, new hair," Williams wrote in a caption on Instagram that accompanied a photo of her new golden, beachy look. "Back to blonde and back to work."

The Biggest, Boldest Celebrity Hair Transformations of 2019

Including inspo from your favorites, including Ariana Grande, Lady Gaga, and more.