Ascending the stage during 20th Century Fox’s presentation at CineEurope this evening, Lightstorm Entertainment’s Jon Landau offered an update on the four upcoming Avatar sequels. Production on the James Cameron-directed pics, which will be stand-alones but together form “an epic saga,” officially begins September 25 with performance capture, Landau told the assembled exhibitors in Barcelona.

The production start date has been somewhat fluid, seeming to jockey over time. In April, when the sequels’ release dates were set, the Avatar Facebook page touted, “Great to be working with the best team in the business! Avatar takes flight as we begin concurrent production on four sequels.”

Landau tonight noted Cameron “has done a couple of sequels before in his career and I would argue that those sequels have lived up to, if not exceeded, the original movies.” That starts, he said, with the foundation of a script and “that’s what Jim has been working on for the last several years… Finally, we have the four scripts for the Avatar films ready.”

During the development phase, “some of the industry’s best artists” have been working on designing a world of these movies, said Landau, who then showed a premiere preview montage of some of the designs of Pandora and its inhabitants.

“At the heart of any movie are the characters,” Landau continued. “One of the strengths of great scripts are always the universal and relatable themes… There’s no more relatable theme than family. At the center of each of our four movies will be the Sully family. Each sequel will play as a stand-alone movie. Each movie’s story will come to its own conclusion… However, when looked at as a whole, the journey across all four movies will create an even larger connected epic saga for audiences around the world.”

While developing the scripts, the decision was made to continue to set the movies on Pandora. “We always knew that Pandora was a place as diverse as Earth,” Landau said. The original cast is reuniting for the films while Landau also noted that Game Of Thrones‘ star Oona Chaplin has joined the cast and will be involved in all of the next movies.

Avatar is the biggest box office hit of all time, grossing $2.7B worldwide. The sequels are set for release thusly: Avatar 2 on December 18, 2020; Avatar 3 on December 17, 2021; Avatar 4 on December 20, 2024; and Avatar 5 on December 19, 2025.