Sam Worthington has revealed some of the incredible physical challenges he endured filming the latest Avatar movie and opened up about one moment of terror.

But the Australian is not bothered by pressure for the science fiction sequel to live up to its record-breaking original.

“I don’t think we approach it with that much hubris,” he told AAP.

“We just try to tell a story that’s expanded on the characters and we hope it connects.”

Tonowari and Jake Sully actors Cliff Curtis and Sam Worthington with the backdrop of the famous Bondi Beach Iceberg Pool (taken over by ATWOW) arrive in Sydney to promote the movie and attend a special 3D screening event for VIP Guests! #Avatar2 #AvatarTheWayOfWater pic.twitter.com/fzj1MBDjWU

— Discovering Pandora (@discoverpandor4) November 21, 2022

The 46-year-old, whose career breakthrough came in the 2009 sci-fi epic, returns as Jake Sully as his family moves from the forest and battles to stay alive on the planet Pandora.

Avatar: The Way of Water is set more than a decade after the events of the first film, which grossed nearly US$3 billion globally and heralded a new era of 3D films and photorealistic computer-generated characters.

Director James Cameron has again blazed new technological trails, taking performance capture underwater to offer the most realistic movements to be expected of 10-foot blue alien creatures.

Avatar: The Way Of Water Behind the Scenes, Actual Scene vs CGI, this photo of Britain Dalton, who plays Lo’ak.#AvatarTheWayOfWater #Avatar #KateWinslet #SamWorthington #ZoeSaldana #SigourneyWeaver #StephenLang #CliffCurtis #JamesCameron #BaileyBass #BritainDalton #JackChampion pic.twitter.com/ISCzpoRzx1

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Acting underwater meant Worthington and his co-stars including Zoe Saldana and Kate Winslet had to master free diving.

Sigourney Weaver, who returns to the series as the biological daughter of her avatar that appeared brain-dead in the first film, was initially apprehensive.

But the now-73-year-old soon began spending up to six-and-a-half minutes below.

“Sigourney is part-fish; it’s pretty incredible,” Worthington said.

“These scenes are hard enough to do on dry land with all the distractions.

“They’re emotionally resonate, very difficult – and we’re crazy enough to try them underwater.”

Sam Worthington and Cliff Curtis#AvatarTheWayOfWater pic.twitter.com/7j12pRdmTU

— Avatar Sequels (@avatarsequelsbr) November 23, 2022

The Terminator Salvation and Fractured actor recalls a terrifying moment during a pivotal scene with Britain Dalton, who plays Sully’s second-eldest son.

“Halfway through, I realised I’m 30 feet underwater, I’m running out of oxygen,” he said.

“My brain starts wigging out, which means my heart rate starts increasing so my oxygen is depleting even more.”

But Dalton’s touch and look helped reset Worthington.

“(It) brought me back into the scene, which is about a father and son connecting,” he said.

“(Filming underwater) wasn’t just a gimmick; we’re trying to take the most powerful scenes you can think of and put them deep-dive.”

The new film is the first of four expected sequels. Filming has wrapped on the second while the first act has been shot on the third.

The Way of Water brings a return to 3D glasses and what director Cameron and producer Jon Landau hope is a fresh outlook on a trip to the cinema.

“I don’t want them to say I saw a movie,” Landau said.

“I want them to say I experienced a movie.”

While plans for Avatar sequels were underway before Cameron’s Mariana Trench expedition, that 2012 trip to the deepest part of the ocean helped inspire creatures now on screen.

Worthington said he received a call about that time from Cameron that the director felt like “going on more of a journey with Pandora”.

That journey begins with the Sully family leaving the forest in search of a new sanctuary.

They find the reef clan of Metkayina – led by Ronal (Winslet) and her husband Tonowari (New Zealand actor Cliff Curtis) – and quickly find difficulty in no longer being top dogs.

“They and their children have to learn to leave this position and learn the way of water and learn how to get along in a totally different environment,” Curtis told AAP.

While the Fear the Walking Dead and The Dark Horse star admits he couldn’t match the lengthy underwater stints of Winslet and Weaver, Curtis appreciated the pared-back nature of performance capture.

“I’ve got no costume, I’ve got dots on my face, a helmet with a camera in front of my nose,” he said.

“So, you can’t hide behind anything.

“It’s just you, Jim and the other actors.”

Being a newcomer to the series, he also rejects comparisons to the first instalment.

“I don’t see it as a sequel as replicating something that was successful,” Curtis said.

“I see it as the next part of the journey.”

Avatar: The Way of Water opens in cinemas on December 15.

AAP 2022