James Cameron and Fox have officially announced that the number of Avatar sequels that have been in the pipeline for a few years now has been upped from two to three, and confirmed exactly who will be coming on board to write them.

The original 2009 movie of course went on to become the highest-grossing film in history with $2.8bn. at the box office, beating Cameron’s previous movie, Titanic, from the top spot that it had held for over a decade.

Talk of two sequels has been continuing in the years since the original’s release, and now Fox and Cameron have committed themselves to Avatar 2, 3, and 4, Deadline report, announcing that Avatar 2 will kick proceedings off in December 2016, with Avatar 3 due in December 2017, and Avatar 4 in December 2018.

Cameron also confirms that the writing duo of Amanda Silver and Rick Jaffa (Rise of the Planet of the Apes) will be writing one film, Josh Friedman (War of the Worlds) will write another, and Shane Salerno (the upcoming Salinger) will be writing the other. Each will collaborate with Cameron separately, and co-write with him. Coming with the announcement, Cameron spoke about the move, saying,

“Building upon the world we created with Avatar has been a rare and incredibly rewarding experience. In writing the new films, I’ve come to realize that Avatar’s world, story and characters have become even richer than I anticipated, and it became apparent that two films would not be enough to capture everything I wanted to put on screen. And to help me continue to expand this universe, I’m pleased to bring aboard Amanda, Rick, Shane and Josh — all writers I’ve long admired –­ to join me in completing the films screenplays.”

Perhaps most impressively of all, Fox and Cameron have set their gameplan to shoot the three films back-to-back, a move of such ambition not seen since Peter Jackson helmed The Lord of the Rings Trilogy in one go.

Said Fox’s chairman and CEO, Jim Gianopulos:

“We at the studio have no higher priority, and can feel no greater joy, than enabling Jim to continue and expand his vision of the world of Avatar. The growing breadth and scale of Jim Cameron’s plans for his magnificent fantasy worlds continue to amaze us all.”