Blake Lively Posts Sultry Dark-Haired Selfie as It's Revealed She'll Star in 'It Ends with Us'

It looks like Blake Lively is getting into character.

The 35-year-old actress debuted a daring new hair color on her Instagram Story Thursday, trading in her blonde tresses for a brunette look.

She revealed the new color in a sultry post that sees her gazing off camera.

Lively's mysterious snap comes after her latest role was announced. The Gossip Girl alum is set to star opposite Jane the Virgin star Justin Baldoni, 39, in a film adaptation of Colleen Hoover's bestselling novel It Ends with Us.

Hoover expressed excitement over the cast in an Instagram video shared on Thursday.

In the clip, she gets emotional as she stands outside of her childhood home and thanks her mother, whom she says the book was "loosely inspired by," adding that her mom "got us out of a scary situation when I was little and brought us here to this house."

After expressing appreciation, she revealed, "Our Lily is going to be played by Blake Lively. Blake Lively, y'all. She's my dream Lily."

As for Baldoni's character, Hoover said, "When I first met Justin Baldoni, who is directing the film for It Ends with Us, I immediately wanted him to be Ryle. I just thought that he had what it takes to play that character. The good news is he's gonna be Ryle. So we have our Ryle and our Lily."

She shared that Lively and Baldoni "have what it takes to bring these characters to life."

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Pointing to one of the home's windows, Hoover told her fans, "The little girl who used to sleep in that bedroom thanks you for all the support."

Clearly excited about the film's cast, she concluded, "Blake Lively, Blake Lively. I can't say it enough."

Baldoni reposted the video, adding the caption, "Here we go!!!!"

The movie will tell the story of Lily, a fresh college graduate who meets and falls in love with a man named Ryle. As the two get closer, an old flame comes back into Lily's life and threatens her and Ryle's growing romance, according to Deadline.

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It is being developed by Wayfarer Studios and Sony Pictures. Baldoni will serve as the director, and Lively will executive produce. Christy Hall is writing the script and will also produce the movie, the outlet reported.

Alex Saks is also on board to produce under Saks Picture Company along with Jamey Heath via Wayfarer Studios, per Deadline. Steve Sarowitz, Andrew Calof and Baldoni will also executive produce for Wayfarer.