The first reviews for the long-awaited Avatar sequel are trickling in – and they’re glowing.

Set 15 years after the events of the first film, Avatar: The Way of Water, will see Jake Sully (Sam Worthington) and Neytiri (Zoe Saldana) and their children battle to keep each other safe and stay alive.

As the title suggests, much of the story will occur in and around the ocean, and will introduce a new oceanic clan of Na’vi called the Metkayina.

The film has big shoes to fill as Avatar broke new ground on visual effects, and remains the world’s highest-grossing film.

But with a 13-year gap between the two movies and the massive amount of money poured into the sequel – it will need to make $US 2 billion ($A2.9 billion) just to break even – there have been concerns Avatar: The Way of Water could be a letdown.

But US film reviewers and Hollywood notables who attended early screenings of the movie say it blows expectations out of the water.

Perhaps the biggest praise for director James Cameron’s latest movie is a tweet from Guillermo del Toro, director of much-lauded films such as Pan’s Labyrinth and The Shape of Water.

Tweet from @RealGDT

Many noted that the storyline was particularly strong – an important compliment, given the flack Avatar has received in the years since its release for its perceived lack of cultural impact and forgettable characters and dialogue.

It looks like no such criticisms have been levelled at its sequel, which has instead been applauded for a storyline that resonates with audiences emotionally.

Tweet from @BilgeEbiri

Tweet from @Klee_FilmReview

Tweet from @ErikDavis

Tweet from @BrandonDavisBD

And if you’re wanting to get the best viewing experience, it might be best to splurge on a trip to the cinema.

IndieWire chief film critic David Ehrlich said the movie was “easily one of the best theatrical experiences in ages”.

“Streaming found dead in a ditch,” he tweeted.

Tweet from @emperorjames

‘Crack the code’

Avatar: The Way of Water, set to make its Australian debut on December 15, took more than a decade to make as director James Cameron discarded several scripts to make sure the sequel was worthy of its predecessor.

“When I sat down with my writers to start Avatar 2, I said we cannot do the next one until we understand why the first one did so well,” Cameron told The Times UK.

“We must crack the code of what the hell happened.”

Shooting the movie, which was filmed simultaneously as the still-untitled third Avatar sequel, took three years.

Post-production to introduce the high-level visual effects required took a significant amount of time as well.

Luckily, audiences won’t have to wait so long for the third film, which is currently set for release in December 2024.

Two more Avatar sequels are planned to follow, but their green light hinges on how well the first two sequels do.

“If we make some money with two and three, it’s all mapped out,” Cameron told The New York Times.

“Scripts are already written, everything’s designed. So just add water.”