Margot's roots are the same colour as her brows, and a stark contrast to her otherwise buttery shade.
So what's going on? Given that the actress is in the midst of a major career moment, we're almost certain it's not a matter of, oops, I forgot to get my hair coloured. So it must be deliberate. Which would tap into the whole "you beauty" direction that beauty has been heading (see: the rash of curl products being launched, alphabet creams that enhance but don't mask skin, and so on).
Traditionally, visible roots have been the kind of thing women were quick to hide, speed-dialling their colourist for an emergency appointment or temporarily camouflaging with coloured dry shampoo. But for those who prefer a low-maintenance (aka, lazy-girl) beauty, the sit-back-and-watch-it-grow approach just got the red carpet tick of approval.
RELATED: Curls gone wild!
Here are a couple of other A-listers who have rocked dark roots with light hair: