Sigourney Weaver is proving she’s ageless in the next “Avatar” movie.

In the new issue of Empire, all about James Cameron’s long-in-the-making sequel “Avatar: The Way of Water”, it’s revealed that Weaver will be playing new teenager character Kiri.

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In the film, Kiri is the adopted Na’vi daughter of Sam Worthington’s Jake and Zoe Saldaña’s Neytiri.

“I think we all pretty much remember what we were feeling as adolescents,” 72-year-old Weaver says of playing the teenage blue alien. “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.”

Talking about the decision to cast Weaver in the role of a teenager, Cameron says, “As an acting challenge, it’s big. We’re gonna have a 60-something actor playing a character [decades younger than] her actual biological age. Sig thought it was all kinds of fun.”

READ MORE: First Teaser For ‘Avatar: The Way Of Water’ Debuts Online, Disney Plans To Re-Release ‘Avatar’ In Cinemas

He also recalled the actress workshopping her performance with a group of teenager girls in order to capture the energy of youth.

“Sigourney just became younger,” Cameron says. “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.”

Weaver had previously appeared in the original “Avatar” in 2009, playing the human character Dr. Grace Augustine.

“Avatar: The Way of Water” opens in theatres Dec. 16, and will also star Kate Winslet, Cliff Curtis, Michelle Yeoh, CCH Pounder and more.