Sigourney Weaver to play new character in Avatar: The Way of Water — see the first image

It's been a big week for news from Pandora.

Details of the long-awaited Avatar sequels have been slowly trickling in. First, we got photos of Kate Winslet in the forthcoming Avatar: The Way of Water.

Now, we have our first glimpse at Sigourney Weaver in the forthcoming chapter of the sci-fi venture — and shockingly, she's portraying an entirely new character.

In an image unveiled Friday, Weaver can be seen as a blue alien teenager, a far cry from the doomed Dr. Grace Augustine she played in the original blockbuster. Another surprising detail is that her new character, Kiri, is a member of the Na'vi and Jake and Neytiri's adopted daughter.

Andreas Rentz/Getty Images; Everett Collection Sigourney Weaver in 2009's 'Avatar'

The photo appears in this month's issue of Empire magazine, which features interviews with the cast and director James Cameron. For Weaver, the role was a chance to relive her adolescence.

"I think we all pretty much remember what we were feeling as adolescents," she told the publication. "I certainly do. I was 5' 10" or 5' 11" when I was 11. I felt strongly that Kiri would feel awkward a lot of the time. She's searching for who she is. I was thrilled to be given that challenge by Jim."

Cameron, who previously teamed up with the star for Aliens, knew Weaver would be up for the immense challenge.

"Sigourney just became younger," recalls Cameron. "She looked younger, she had more energy, and she never quite stepped out of Kiri for our whole capture period. She had a glow on her face and lightness in her step and a fun spirit."

Avatar: The Way of Water picks up over a decade after the events of 2009's Avatar. Zoe Saldaña's Neytiri and Sam Worthington's Jake will be featured in the production, along with their new family.

The story will center on "the lengths they go to keep each other safe, the battles they fight to stay alive, and the tragedies they endure," reads the film's official synopsis.

Stephen Lang is also slated to return to the franchise, while Cliff Curtis, Joel David Moore, CCH Pounder, Edie Falco, and Jemaine Clement are new to the cast.

See Weaver as her new character in the Empire tweet above.

Avatar: The Way of Water will be released in theaters Dec. 16.

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Related content:

• Breaking down the images and implications of the Avatar: Way of Water trailer

• Zoe Saldaña says Avatar 2 return is humbling and exciting: 'The wait is finally over'

• Avatar 2 footage at CinemaCon reveals oceanic vistas and Na'vi family dynamics