The Superman Returns actress was spotted rocking her new 'do in snowy Manhattan yesterday (4 March) on the set of her new film, Still Alice.
Kate wrapped up warm in a long navy puffer jacket, lace-up brown boots and black tights while braving the freezing temperatures in the Big Apple.
Her hair was swept back into a messy bun and she flaunted a flawless English rose complexion with a petal pink pout.
Kate - who is married to American director Michael Polish - has been various shades of blonde ever since we can remember, so it's certainly a change to spot her rocking such a different hairdo.
The starlet also took to Twitter last night to showcase her new bonce, posting a snap along with the caption: "Strawberry Fields #StillAlice."
The 31-year-old actress stars alongside Kristen Stewart and Julianne Moore in the movie, which tells the story of a psychologist suffering from early-onset Alzheimer's disease.
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