After it became the highest grossing movie of all time, director James Cameron decided that he was going to devote himself to making nothing except sequels to Avatar for the rest of the 2010s. Now, it seems that he might have put himself in a spot of bother by writing too much material.

Composer James Horner, who worked with Cameron on the first Avatar movie in 2009 as well as on Aliens and Titanic, told film website that the director is trying to condense screenplays for four sequels into three so he can fit them into the planned release schedule.

James CameronJames Cameron might have trouble condensing four scripts into three 'Avatar' sequels

He revealed: “Right now Jim has four sequels, script wise. And he's trying to make it into three. And that is where, I think, his effort is going right now. To keep it to three sequels. Because he's got so much going on, how do you keep it from expanding into yet a fourth movie - a fifth movie, total. And he'll get that sorted out.”

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Admittedly, it isn’t clear whether there’s a serious problem with editing out material, and hinges on Horner believing that Cameron wants to stick to three sequels. After all, many movie franchises have their final instalments divided into two movies in order keep the income stream flowing, so why not Avatar, the most successful movie ever?

If not adjusted for inflation, the first of the sci-fi epics became the highest grossing movie in history, with global box office takings topping $3 billion, winning three Oscars in 2010. The sequels have been a long time in the making, and the first was expected to hit cinemas in 2016, but this was recently pushed back a year.

The third Avatar is scheduled for 2018, and the fourth (possibly called Av4tar) for 2019.

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