The Wolf of Wall Street star's blonde locks were nowhere to be seen at Sunday's Oscars as she joined all manner of gorgeous A-listers at this year's glitzy event, held at the Dolby Theatre in Los Angeles.
Margot showed off a cheeky snap earlier in the evening, giving us a glimpse of her new do while she was having her hair and make-up done in preparation for the event.
"Never thought I'd say this.. I'm getting ready for the #oscars!!!!!" Margot tweeted.
And judging by that huge grin on her face, we can see that she was very happy to be taking her new hair to the awards.
We have to admit, we loved Margot as a blonde, but when someone's hair looks this glossy when it's dyed a beautiful deep brown, it's hard not to love it even more.
Margot rocked her new do with heavy brows; simple eye make-up and rich, plummy lips – a look she probably wouldn't have gone near had she still been a bright, sunny blonde.
She also wore a beautiful floor-length black YSL gown, with a huge oversized bow on the back and embellished with sparkles across the body.
Definitely one of our favourite red carpet looks of the evening...
Margot starred opposite Leonardo DiCaprio in The Wolf of Wall Street which was nominated for Best Picture at last night's Oscars.
And the Australian actress is becoming a bit of a fashion and beauty icon here in the Reveal office.
We can't wait to see how she works this new darker hairdo on the red carpet and are envisioning all manner of bright colours and strong make-up looks.
Bring it on, Margot!
Oscars 2014: Red carpet dresses!
Copyright: Rex Features Startraks Photo
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