If you're making a movie whose hook is the 3D IMAX experience, why would you release the first footage on the internet, where everyone would complain about how ho-hum it looked? According to Sam Worthington, James Cameron did it on purpose.

Talking with journalists on the London set of his next film, Clash of the Titans, on Avatar Day itself, Worthington said that the disappointment felt from the teaser would soon vanish.

'It has a hell of a lot of hype. I read what was said yesterday about the trailer, and I can see their point, but it's not built for an Apple Mac. It's built for IMAX. It's built for 3D. It's what he's designed it for, he's designed it to bring people back into the cinema.'

So why the heck would he release that trailer first, Sam? 'It's interesting that he's released that trailer, that Jim's gone and done that, and the next day he's releasing it on IMAX. From one extreme to the other - we get criticism and then we get rave reviews. That's obviously going to get people to think and go, 'Damn right, I'm going to see this at the cinema.' That's what Jim's always said to me, that he wanted to bring people back to the movies, and he's a smart enough man to be that tactical.'

Worthington adores Cameron, it seems. While other actors who have worked for the director moan about the experience, Worthington beams. 'Ultimate collaborator. He's the boss, he has final say, but he says, 'Gimme what you got.' First thing I said to him was, 'I've got nothing to lose, so I'll give you everything.' I threw everything at him, every idea, and he'll whittle it down to what he wants. That's your job, to offer. The guys designing one of the plants or the spaceships would give him a thousand different designs and he would whittle it together to get it his stamp.'

Interestingly, Worthington also differs from many actors in another regard. While his colleagues may talk about how hard it is working on a green screen, Worthington actually prefers it to working on big, physical sets like he has on Clash of the Titans.

'There's nothing. It increases your skills, takes you down to the essence of what acting is, which is reacting. It's more of a challenge since you've got nothing. Jim's very clever; in Avatar you would never act to nothing - if there's an explosion, Jim would throw stuff at you. Or he'd hit you with a big stick to propel you across a room. Or fire a gun so there was the sound of it. He would always give you something to react to, and the challenge would be to find something to make it true. And it brings you back to the basics, which is that it's just you and another person. There's no distractions. You're trying to get something off the other person, and they're trying to get something off of you. I love that.'