The pair have been working together for years, with Garvin’s unique mix of skills proving very valuable to the Titanic director.

“For the last 10 years or so I’ve been running the expeditions and helping Jim with his films,” he said.

“Anything to do with underwater films, I’ve been in charge of safety and in charge of organising and project managing.”

He’s also written several screenplays for Cameron.

Part of the Sydney exhibition is dedicated to these films including the Deepsea Challenge where Cameron, Garvin and a team of engineers reached the deepest part of the world’s ocean – the bottom of the Mariana Trench, known as Challenger Deep.

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“It was the first full ocean depth submarine that had been built since 1960 … and built by mainly an Australian team,” Garvin said.

This craft, the Deepsea Challenger submersible, in 2012 became the second manned vehicle to plunge 11,000 metres to reach the lowest point of the Mariana Trench off Guam.

“Before that I was also involved on Sanctum,” Garvin said.

“I wrote the screenplay on that and was in charge of the diving on that. It was kind of a gritty, survival thriller starring Richard Roxburgh in 2010.”

Over the past year the Bulli local has been travelling back and forth to Los Angeles, working on the four new Avatar sequels. The first of which is scheduled for release in 2010. But for now, Garvin is keeping tight lipped and wouldn’t reveal any more on those projects.

James Cameron – Challenging the Deep is at the Australian National Maritime Museum in Sydney until January 30, 2019.

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