It has been several years since director James Cameron released "Avatar" and revolutionized 3D technology for cinema and he has been working on its four sequels for some time. During this year's recent San Diego Comic Con, the director finally gave an update on the writing process and why the franchise has grown to the point of four more sequels.

Speaking to Screen Rant, the director confirmed that he had just finished the script for "Avatar 4" and that he is still polishing the script for "Avatar 5" given that the draft had been penned by a different writer. The story for the "Avatar" sequels all stem from Cameron and it is a given that he will be the one to work on the final edit of the screen plays.

"The 'Avatar' story arc was originally meant to be a trilogy, but I overwrite, and my writers overwrote as well," the director told Variety during Comic Con. "But basically the first of the sequels cloned itself and became two films, so now it's four films. And the studio's very happy with it."

Cameron did state that the studios see the potential to earn a lot of money but each film will also cost a lot of money to produce so it is a double-edge sword. The first film, back in 2009, earned over $2.9 billion worldwide and is still the highest earning film in history but many critics point out that it earned as much due to repeat releases in theater and because 3D film-viewing was a new novelty at the time.

As of the time being, the second film to earn early as much is "Titanic," which James Cameron also directed, followed by "Star Wars: The Force Awakens."

"Avatar 2" is still scheduled for release by the holidays of 2018 and each sequel will follow every year up to 2022 or 2023, depending on delays.