DRESSED in a navy blazer and pale blue shirt, his beard streaked with white, Oscar winner Jeff Bridges looks less like a sci-fi hero battling the evil forces of artifical intelligence, and more like Father Christmas in his Sunday best.
So it's hard to imagine the distinguished 61-year-old wearing what he describes as a "white leotard with dots" to shoot part of his role in the long-awaited sequel to the 1982 cult high-tech adventure Tron.
Almost 30 years after the original, Bridges is reprising the character of Kevin Flynn in Tron: Legacy, but he's also undergone something of a digital makeover to play a younger version of himself and Flynn's enemy Clu 2.0.
"It was amazing," says the actor of the first moment he saw his digital self. "I can play myself at any age now."
Back in the Eighties, Tron – the tale of computer whizz Flynn who gets sucked into the digital realm – was hailed as a defining moment in special effects, using a groundbreaking combination of live action and computer-generated imagery.
Fittingly, Legacy owes a lot to the original – and showcases just what technology is capable of now, with a complex mix of digital motion capture and 3D.
"The original was shot in 70mm black and white and the set was made of this black stuff, duvetyn, with white adhesive tape – that was the Grid. Then it was sent over to Korea to be hand-tinted, frame by frame," explains Bridges.
"But this one, making movies without cameras... wow man! What an idea! That's one of the reasons I wanted to come on board, to experience motion capture," he admits in his familiar drawl.
"I was curious and it was bizarre to work in a room where, instead of a camera, they had these little sensors all over the place, aimed at me, and I'd be in a white leotard with black dots, then a helmet with four antennas shooting my face."
The action starts a few years after Flynn's adventures on the Grid, the computer gaming world from which he eventually escaped to take control of Encom, the software firm he founded.
A strangely familiar man is sitting on his son's bed, telling stories about his breakthroughs in the world of computer gaming.
The man is Flynn, who has the voice of Jeff Bridges, but looks 30 years younger.
Years later, Flynn's 20-something son Sam enters the Grid to find his father, who's become trapped in the computer world, and meets Clu 2.0, a programme madein Flynn's own (younger) image, who's turned against him and now has control of the Grid.
To create the stunning effects, Bridges was scanned in 3D and a performance mask was created with 52 markers to capture his facial movements.
Photos of him in his early 30s were scanned in and correlated. When playing Clu and the younger Flynn, Bridges wore a Helmet Mounted Camera (HMC) which captured his facial movements, so the digital Bridges was controlled by him.
For the actor, it was as though life were imitating art: "One of the wild moments in this movie was when I was scanned initially to get my body into the computer – it was like something out of the first Tron, but except this time it was for real."
As exciting as he found this "groundbreaking" new technique, there was a down side for Bridges.
"I like relating to the lens and I like having a costume and a set – they're grounding. So much of making a movie is about creating an illusion – and the first person you have to create the illusion for is yourself. So when I have a costume and a set, that helps me into those times and that character.
"When you don't have that, it's like being a kid without all the cool gear – you have to use your imagination."
Bridges admits he initially had doubts about making a second Tron film: "I have a lot of hesitation making any kind of decision in my life, I'm really slow at it. But I did think, 'Are they going to be able to pull it off?'"
It helped that Steven Lisberger, the director of the original (who Bridges describes as Tron's "godfather"), was back on board as a producer: "We would always go back to him and say, 'Is this consistent with the myth you started?'
"Having Lisberger on set felt like we'd just had this long weekend after the first one and we were back doing the same work, it was crazy."
After surviving some of Clu's gladiatorial games, Sam finally finds his father at a safe house off the Grid, dressed in white and meditating.
"One of my concerns was that this would just be a special effects movie. I wanted to add some Zen mythology," says Bridges, who has studied Buddhism.
"I figured (it made sense] with Flynn's past and what he encounters on the Grid coming in, being full of himself and thinking he can beat Clu.
"As he says in the movie, the more he goes against him, the stronger Clu becomes, so he decides just to stop and see if the weather and the universe will change by itself."
Flynn realises he's become physically trapped by his own search for perfection, when there's actually no such thing: "You can be a prisoner to your own preferences. The idea that, 'I want it the way I want it' can lead you to a really dark place. You've got to watch that, you know what I'm saying?"
Bridges appears to embody the Zen ideal. He has bided his time in Hollywood and, after four previous nominations over 40 years, finally won a best actor Oscar this year for his role as a country singer in Crazy Heart. Not that he's really had much of a chance to enjoy it.
"I think it has changed my life, but I haven't figured that out entirely, because about a day after the Oscars I went to work on True Grit, so I got back into work mode and I've been working ever since."
And with that, he's off to promote Tron: Legacy some more.
Tron: Legacy is on general release. Tron revolutionised special effects in the computer-mad 80s, the film's star Jeff Bridges tells Kate Whiting why he was happy to rewind the clock for the 21st-century remake.
The real legacy of a cult classic
Tron, the original 1982 sci-fi classic, gave teenage boys the chance to live the video game
To do it, writer and director Steven Lisberger combined groundbreaking special effects with an unimaginable set of weapons, high-tech suits and lightcycles.
After dreaming up a digitised world of gaming battles for the new generation of geeks, who dreamed of their computer coming to life, the special effects world followed
The original Tron was populated by characters like RAM and Bit (who could only answer in binary). It might seem outdated now, but in 1982, the film was at the forefront of computer wizadry.
system upgrade: Tron:Legacy is a showcase for what the special effects technology inspired by the first film is now capable of.