The 67 year-old revealed that the franchise's next journey will bring us to the sea, combining the director's love for the ocean with his film-making.

It's been a long journey from the first 'Avatar' film to the second for James Cameron.

"It sounds kind of nuts, the process," the director said. "I mean, if 'Avatar' hadn't made so much damn money, we'd never do this, because it's kind of crazy."

Speaking to Entertainment Weekly, Cameron talked about how the second movie will try to scale new heights, which is no mean feat. 'Avatar' is once again the highest-ever grossing film in the history of cinema.

The theme for 'Avatar 2' is centred around family. Set 14 years after the events of the original film, it focuses mostly on the offspring of Jake Sully (Sam Worthington) and Neytiri (Zoe Saldana) after they have settled down.

"Ultimately, the sequels are a story about family, and the lengths parents will go through to keep that family together and keep them safe," producer Jon Landau explains. "I always say that Jim's movies have universal themes — and really, there's no more universal theme than family."

On the sequel's setting, Cameron mentions that it will take place in a more marine environment, as opposed to the rainforest from the original flick.

"I do the ocean thing when I'm not making movies," he says. "So if I could combine my two greatest loves — one of which is ocean exploration; the other, feature filmmaking — why wouldn't I?"

Making a film involving underwater scenes, it was important for Cameron to make it look realistic. A special 900,000 gallon tank replicating the moving ocean was built for the actors to work in.

"My colleagues within the production really lobbied heavily for us to do it 'dry for wet,' hanging people on wires," Cameron explains. "I said, 'It's not going to work. It's not going to look real.' I even let them run a test, where we captured dry for wet, and then we captured in water, a crude level of our in-water capture. And it wasn't even close."

'Avatar 2' is undoubtedly a highly-anticipated movie. However, the 'Titanic' director still has reservations of its box office performance in a post-pandemic world.

"The big issue is: Are we going to make any damn money?" Cameron says of his planned sequels. "Big, expensive films have got to make a lot of money. We're in a new world post-COVID, post-streaming. Maybe those [box office] numbers will never be seen again. Who knows? It's all a big roll of the dice."

'Avatar 2' releases in 2022. The third, fourth and fifth movies in the franchise come out in 2024, 2026 and 2028 respectively.