The star teased her followers with a trailer for The Undoing on Instagram and in the process got them talking about her ringleted, red locks.
Nicole - who plays Hugh Grant's wife in the drama - looked stunning in just about every scene with her long tresses looking decidedly darker than usual.
WATCH: Nicole Kidman and Hugh Grant tease fans with trailer of their new HBO show The Undoing
"Red, curly haired NK is the best Nicole Kidman," said one fan, while another wrote: "Your hair is beyond gorgeous."
Others couldn’t help but comment on her age-defying appearance and wrote: "Nicole told age to leave her alone. She looks AMAZING" and "NICOLE KIDMAN forever young".
The show - which will air on HBO on 25 October in the US - is a psychological drama and focuses on a successful woman, played by Nicole, whose life unravels after her husband disappears and leaves a trail of tragedies, including a murder, in his wake.
Nicole has been sporting blonde hair recently
Nicole is reunited with Big Little Lies creator David E. Kelley for the project which is set to be a huge hit.
The actress previously shared a scary new look with fans to promote the show. She was standing at the top of the stairs, wearing a green dress and staring menacingly down the lens.
Her fans informed her that she looked terrifying, but still swore to tune into the show when it airs.
Nicole teased fans with a scary photo
Nicole is equally as buzzed for the release and told the network: "David has created another propulsive series with a fascinating, complicated female role at its centre."
There’s high hopes for a third season of BLL too and in a recent interview published in HELLO! Nicole talked about the prospect of working with the esteemed cast again: "We'd love to do it," she said.
"It's lovely when you have two seasons to have the possibility of another and to spend all of that time together and enjoy it. That's exceptional."
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