She was photographed on the set of her new film Still Alice showing just how you can make the switch, the classy way.
Helen Flanagan recently dyed her hair red, it was not quite so successful.
It was basically purple.
She's not the only one to go for a dramatic new look - Margot Robbie has gone raven haired.
Maybe it's just because Kate's got a great face, but the combination of porcelain skin, soft pink lip and that auburn do is totally working for us.
What do you make of Kate's hair?
Love it! 86.67%
It's nice but the blonde is better for sure.6.67%
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HELEN FLANAGAN, IS THAT REALLY YOUR FACE?
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