Imagine the scene: you're enjoying a scenic drive through lush Hawaiian mountains when you see a man, near-naked and sporting a tail and ears, chasing a woman - in similar attire - through the rainforest.
You then notice a man with a handycam filming them. How odd.
Then, imagine, you ask the pair what's going on and are told - totally straight-faced - that they're making a movie. And the guy with the handycam is James "King of the World" Cameron.
You wouldn't be blamed for thinking things had gone a bit wayward since Titanic.
But rest assured, Cameron has not lost the plot. Rather, the curious scene was part of his meticulous preparation for Avatar, a film set to be the most technologically advanced - and expensive - made.
Australian actor and star of the piece Sam Worthington explains the filming process, which took more than 14 months and began in the Hawaiian rainforest, where Worthington and his leading lady Zoe Saldana learnt to become the Na'vi - an alien species at the heart of the film, who inhabit the planet Pandora.
"Pandora's like a rainforest so to go to Hawaii was our rainforest experience. We'd do scenes in the rainforest so [Cameron] could see how the light hit our faces, so the computer guys had references. Also, it gave us a feeling."
After two weeks rehearsing in the rainforest, production began in the motion capture space known as The Volume - essentially an empty sound stage where the actors had nothing but their imaginations to work with.
"The best thing about making that movie was you never got used to it. Each day was about figuring out its own little problems," says Worthington gleefully.
"You're not only creating the technology, we're figuring out what we're meant to be doing. None of us knew how to swim in The Volume. When there's nothing there, how do you swim?"
Cameron's 3D feature is one of the most ambitious cinematic experiences embarked on, rumoured to have cost more than US$230 million ($322.7 million).
If that's wasn't enough to have accountants sweating, there was the small fact that, three weeks away from release, the film wasn't completed, and Cameron was quoted as saying the film was to be in editing right up to delivery time.
Worthington jokes he'll be back in his motion-capture suit the day before the premiere, reshooting scenes for Cameron.
"He's detailed, he's meticulous. It's his movie and he knows what he wants. The level of excellence that man wants, I've never met in any other director. It's why he's Jim Cameron. It's why his movie is the highest grossing movie of all time. He's a visionary."
The vision for Avatar first surfaced in 1994, when Cameron wrote a treatment for the film. But he later abandoned the project when he realised the technology didn't exist to bring the world of Pandora to life.
It is an extraordinary world of shimmering, technicoloured creatures swooping and soaring out of the screen - and one that finally came to being with the help of Weta Digital and the technology first seen in Lord of the Rings.
The cat-like, computer-generated Na'vi smirk and sneer as well as any human actor, thanks to special headgear, which saw tiny cameras pointed at the actors' faces, recording every muscle movement.
"I can't describe what the immersive 3D did but suddenly the grass looks real. We filmed that in a grey sound stage. [Jake's] got my walk, he has my smirk. It's mind boggling even for Jim," says Worthington.
Traditional actors might have found such contraptions off-putting but Worthington embraced the new technology.
"I loved it, I found it liberating. I loved going into The Volume. The head cam was a new thing. It had only been used briefly with Andy Serkis [Gollum in Lord of the Rings] and my first one kept slipping. No one could figure it out. Then they worked out the weighting of my head - my head's a bigger melon than most! - so they had to weight it differently.
"I got a drill and drilled holes in it because I was boiling up. I'm doing 16 hours in this thing; the heat's got to come off. Jim went, 'That's what I want! I want people to figure this out'."
The technology is certainly impressive but Worthington insists it is the characters and the story that will really appeal to audiences.
"You're trying to get to the heart of these people otherwise all the bells and whistles in the world aren't going to tell a good story.
"Jim's the best at that. He can sink a boat better than anybody but the reason we kept coming back was because of Jack and Rose."
Worthington isn't exactly the Leonardo DiCaprio type, though his profile is sure to rise in the wake of Avatar. Sporting two-day-old stubble and a nasty looking grazed knuckle, the cheeky Aussie swears like a sailor and greets people as "youse guys". Ask him how he got the job on Avatar and he'll grin and tell you, "Because I'm cheap".
Worthington has long been regarded as one of Australia's rising acting talents, with more than a decade's worth of work to his name, including roles in Bootmen, Dirty Deeds and the critically acclaimed series Love My Way.
At 33, he is no wide-eyed naif. Which is what, he believes, drew Cameron to him.
"I've always said you do as much in your own country so when you go and play with the big boys, you've done an apprenticeship and you're not wasting their time.
"I was 30 years old and going through a time in my life to say, 'Look, I'm a man, you're a man. If you're wasting my time, I'll leave. If I'm wasting your time, get rid of me'.
"If this had happened when I was 22, you'd be too starry-eyed and not grounded enough. This came at exactly the right time where I was like, 'Mate, I'll give you everything I've got but I'm not sucking up to you'. That's what Jim respects and that's what Jim demands."
Cameron isn't the only one to appreciate Worthington's direct approach. Since making Avatar, the Australian actor has been overrun with offers and has another three films due out next year, on top of his turn in Terminator Salvation, which was released earlier this year despite being filmed after Avatar.
"Jim Cameron changed my life. He got me in the game in regards to big Hollywood movies. But I always think there's no difference between a massive blockbuster like Avatar and a smaller independent domestic drama. My job's not going to change."
The film is Cameron's first feature since 1997's Titanic, which took home 10 Oscars and still holds the title of the highest-earning film on record. So it's only natural people are interested to see what he's been working on all this time.
Combined with the promise of never-before-seen special effects and the exorbitant budget, Avatar is easily the most anticipated film of the year - expected to topple even Twilight's mega box office takings.
But Worthington says that is not his concern. "I'm the actor. My pressure is to give my director what he wants. That's up to the moneymen who count the beans. They're probably sweating bullets. Hopefully, if I've done my job correctly, they should feel confident."
But the actor will admit he is only just realising the size and power of the juggernaut he is on.
"When you're filming it, Jim protects you from all of that and so you just do your job. You're in the eye of the hurricane so it's all very calm. Now we're starting to stick our heads out a bit and we're getting a bit of windburn now and then.
"Any movie's going to have hype, this one's going to have exponentially more so because of who's creating it, his last movie's success and the amount of money that we've supposedly spent on it.
"You can sell it on the hype or you can sell it on the experience and I think the experience is going to stand by itself."
The world of Avatar
Because Pandora's atmosphere is toxic, the RDA has created the Avatar programme in which humans have their minds linked to a remotely controlled, genetically engineered Na'vi-human hybrid grown aboard a spaceship laboratory on the five-year journey to Pandora from Earth. One of the new controllers is Jake Sully, a former marine confined to a wheelchair who has been promised a cure for his paraplegia if he succeeds.
Jake's Avatar mission is to infiltrate the Na'vi but he also has to look out for Pandora's other creatures like the Banshee, the Thanator and the pterodactyl-like Great Leonopteryx Jake's Avatar is rescued by Neytiri, a beautiful Na'vi female, and he is taken in by her clan. He learns to respect the Na'vi way.
But war with the forces of the RDA - with its fleets of vertical take-off AT-99 Mosquito Gunships bringing back memories of a certain much-filmed 20th-century Asian jungle war - is looking increasingly inevitable. Jake is torn between his new virtual life and his loyalty to his mission. Pandora is the fifth moon of Polyphemus, the second of three gas giants orbiting the star Alpha Centauri A. Polyphemus is slightly smaller than Saturn and has 14 moons. It is inhabited by the Na'vi, who in the year 2154 are the only known species outside Earth to have human-like intelligence.
They are expert hunters, are four times stronger than Earthlings and nearly twice as tall. Pandora's rare mineral Unobtanium - which has magnetic qualities causing it to levitate - has been found to be the possible solution to the Earth's energy crisis. But the Resources Development Administration's plan to mine Na'vi territory has brought the two worlds into conflict.
The Weta factor
Director James Cameron raided Peter Jackson's toolboxes - Weta Workshop and Weta Digital - in the making of Avatar. The workshop designed props and weapons for both the Pandora resident race, the Na'vi, and the invading Earthlings of the RDA. And Cameron shot the bulk of the film's hi-definition 3D shots against green screens on Wellington soundstages.
But much of the film's heavy lifting was done by Weta Digital. Their groundbreaking work on Gollum in Lord of the Rings and on King Kong convinced Cameron to believe that they could breathe life into his creations - taking the actors' motion-captured performances and making them the tall athletic Na'vi.
That meant the animators sometimes had to embellish a little, such as when Neytiri's (Zoe Saldana) tail lashes or her ears lower in anger.
It was not until Cameron and his cast saw the first finished scenes coming back from Wellington that they realised how revolutionary the movie was going to look.
Especially as Avatar goes a step further, by placing photorealistic characters into a world that is also computer-generated.
The surreal landscape and its flora and fauna was created and rendered in the Weta Digital computers, requiring more than a petabyte (1000 terabytes) to store all of the film's CG "assets". By contrast, Cameron's Titanic required two terabytes to create (and sink) the ship and its thousands of passengers.
As well, Avatar was made in stereoscopic 3D requiring Weta to work in 3D in creating their CG scenes, as did other visual effects contributors to the movie like Industrial Light & Magic.
Said Avatar producer Jon Landau about the film's New Zealand connections: "We did not come here for the location. We came here for the craftsmanship and the artistry."
Who: Sam Worthington
Born: August 2, 1976 in Perth, Australia
What: Plays Jake Sully, a paralysed former marine who signs up to the Avatar project and is transported to the planet Pandora.
When: In cinemas December 17.