It's fairly obvious when you first set eyes on Avatar: The Way of Water that this is possibly the most ambitious film ever attempted. And then you realise that James Cameron, the mastermind behind the world of Pandora, has made three films at once.

It's a testament to the man's genius, and perhaps madness, that he even considered doing this. The Way of Water, the entirety of Avatar 3, and the first act of Avatar 4 were all filmed at exactly the same time. There was good reason for that, as Cameron revealed to Entertainment Weekly. With such a young cast joining the film, he wanted to avoid the pitfalls of taking the audiences out of the film if they couldn't believe in what they were seeing. For example, Jack Champion, who plays Spider - a human character - was cast when he was 12 years old. He is now 18, and the films are still shooting.

"I love Stranger Things, but you get the Stranger Things effect where they're supposed to still be in high school, and they look like they're 27. Jack Champion shot up like a weed when we were with him. We shot with Jack when he was 14 and 15, almost up to 16. So we were shooting him over an 18-month period."

Stranger Things Season 4

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The issue of the pandemic brought on further complications. Cameron had to appeal directly to the government of New Zealand to allow the young actors back into the country before they were too old to keep shooting. "I was imagining scenarios where we don't go back to work for a year and a half, and we're completely screwed because he's aged out, and then we have to go back and reshoot with another guy. It was like, 'Just hand me the shotgun.' But fortunately, it didn't work out that way. We were able to appeal to the New Zealand government to let in a small group of our key actors so that we could bring the production back."

The issues of the actors aging out of their roles have been resolved with a plot development after the first act in Avatar 4. "We end the first act in Avatar 4 with a big time jump. We jump as many years as we need to jump. Page 35 of the script in movie 4."

While these were all absolutely valid points from Cameron, it may also be pertinent to point out that he also had no issue casting a 73-year-old Sigourney Weaver as a teenage girl. But of course, the mad genius that he is, he's made it work.

Avatar: The Way of Water is playing in theaters now. Check out our interview with Cameron down below.