During 20th Century Fox's CineEurope presentation in Barcelona, Spain today, producer Jon Landau announced that a new cast member has been added to all of the highly-anticipated Avatar sequels. The producer revealed that Oona Chaplin, perhaps best known for playing Talissa Stark in HBO's Game of Thrones, has come aboard to play a very important character named Varang. While no specific details about Varang were given, she will appear in all four sequels.

Variety reports that Varang was described by Jon Landau as, "a strong and vibrant central character who spans the entire saga of the sequels." She joins another new character who has recently been confirmed, Cliff Curtis as Tonowari, the leader of the Metkayina, a reef clan from Pandora. It hasn't been confirmed if there is any connection between Varang or Tonowari, but it's possible that they could be part of this same reef clan. Director James Cameron has hinted in the past that his sequels will take place underwater, but there still haven't been any official plot details given yet.

Also returning from the original movie are Sam Worthington as Jake Sully, Zoe Saldana as Neytiri, Stephen Lang as Colonel Miles Quatrich, Sigourney Weaver as Dr. Grace Augustine and we most recently got confirmation last month that Joel David Moore will be back as Norm Spellman. We reported in January that motion-capture production will begin this August, but then a few months later, James Cameron pushed the release dates for all four sequels back, with Avatar 2 arriving on December 18, 2020, followed by Avatar 3 on December 17, 2021, Avatar 4 on December 20, 2024 and finally Avatar 5 on December 19, 2025.

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When the first sequel arrives in December 2020, it will be 11 years after the first Avatar movie hit theaters, en route to shattering box office records. While its domestic record of $760.5 million was broken in 2015 by Star Wars: The Force Awakens ($936.6 million), its worldwide record of $2.7 billion remains intact, with the $2.02 billion international tally also still a record. Despite the lengthy gap between sequels, director James Cameron revealed in an interview that he wasn't worried about the time gap, since he often has sizable gaps between his films, including the 12 years between his Best Picture winner Titanic and Avatar.

James Cameron is directing all four sequels, working with new writers on each of the sequel's scripts. The filmmaker worked with Josh Friedman and Shane Salerno on the screenplay for the first Avatar sequel, with Rick Jaffa and Amanda Silver joining Shane Salerno and James Cameron on Avatar 3, and Shane Salerno and James Cameron writing both Avatar 4 and Avatar 5. It remains to be seen how many other characters still need to be cast in Avatar 2 and the rest of these sequels. Oona Chaplin had small roles in Quantum of Solace and The Devil's Double before she was cast as Talissa Stark in Game of Thrones. She has since gone on to star in the mini-series The Crimson Fields, movies The Longest Ride and Dancing For My Havana, and the recent FX series Taboo.