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Fox's vivid indigo-ebony shade is hard for most women to pull off. "The common mistake is to go too dark," Papanikolas says. "While it can look sexy on a young girl like Megan Fox, it can also be severe and harsh." Before making a drastic color change, Papanikolas advises rebuilding the hair with a reconstructive pack to fill the cuticle and create an even surface for the color to adhere.