The cast of the upcoming Avatar sequels just grew by one. According to TheWrapGame of Thrones actress Oona Chaplin has joined the sci-fi franchise.

Plot details are currently being kept under wraps, but Chaplin's character Varang is said to have a "key role" in the Avatar sequels. She is described as a "vibrant central character who spans the entire saga of the sequels." James Cameron previously revealed that, while each installment will tell its own story, they will all serve as one complete saga. Chaplin will also join Zoe Saldana, Sigourney Weaver and Sam Worthington, who are all set to reprise their roles for the sequels.

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Chaplin, the granddaughter of film icon Charlie Chaplin, recently starred in FX's Taboo alongside Tom Hardy. Prior to Taboo, she played Talisa Stark on HBO's hit Game of Thrones. Chaplin's big screen credits include The Longest Ride and What If.

The highest-grossing film of all time, Fox’s Avatar earned nearly $2.8 billion worldwide and was nominated for nine Academy Awards; it went on to win Oscars for Best Art Direction, Best Cinematography and Best Visual Effects. Avatar 2 is scheduled to hit theaters on December 18th, 2020.