Rooney Mara has always been one to take a hair risk, but we never thought we'd see the day she went solid blonde. For the past four years, Mara has kept her strands in their natural brunette hue, then this week, she was spotted in a dramatically different platinum tone. No word yet if it's for a role or not, though it's likely considering that she got a set of ombre hair extensions back in 2013 to film Side Effects, and she's partial to her former deep brown tone. "I've been lighter, but I prefer being brunette," she previously told InStyle. "I find that people with dark hair don't need to wear as much makeup." In line with her minimalist beauty looks for sure, but we can't help but anticipate the Game of Thrones-esque Khaleesi updos she'll likely pair with her pale platinum color on the red carpet. Take a closer look at her new 'do in our gallery, and see more celebrity hair makeovers!