CHRIS Hemsworth has had to bulk up to play Thor an incredible eight times, and his body has started to act very strangely to the changes.
When I sit down to chat with him about his latest outing as the Asgardian God, it's impossible not to notice a weird thing is happening to his muscles - his biceps are constantly twitching.
I tell him this, and he laughs.
"Well, yes, they've got a mind of their own, I know."
He admits to pushing his body hard to transform into the Marvel favourite. "I'm eating every two hours so it's not just the working out part."
With the strong prediction that the upcoming movie, Thor: Ragnarok, will rake in over a billion dollars at the box office, Chris Hemsworth is at the peak of his career.
But the former Home and Away star hasn't let it go to his head.
"I think every actor feels like an underdog. For me, it's a huge mixture of complete fear and then trying to convince myself that I am completely confident. And so you try to fool yourself," he explains.
Evidently, the A-list movie star hasn't forgotten that his was not an overnight success. "Every time I went up for a role, more often than not I would get knocked back. That was my life for the first seven years of being in LA. I felt like an underdog, which I think is a pretty common Australian attitude."
We are standing at the side of a makeshift stage at Oxenford, at the Village Roadshow Studios on the Gold Coast.
Decked out in Thor's new attire, he is suited up as a gladiator and readies himself for a battle scene which kicks off when The Hulk chases him through the streets of planet Sakaar, on which he is held captive.
A makeup artist is applying powder to his face as we chat. Devoid of his signature long blonde locks, he offers, smiling, "I do not miss the hair. Especially at five AM when it takes an extra hour to put it on. The hair was part of the transformation when Thor gets thrown into this gladiatorial world. Believe me, I am really happy about it but there is probably 30 per cent of the film when I have the wig on. Those are not my favourite days."
It's not only his physical appearance which has changed. The great god of Thunder is without his iconic hammer and has to rely on his own brute strength.
"Thor is a little lost at first without it, and I think it's that classic assumption that it's the source of all his power, whereas it's about the journey for him to realise that that's wrong. It's always been within him and the hammer was just an instrument.
"Thor ends up in a world where he is as strong as everybody else and so his abilities don't stand out. No one knows or cares about his history or that he's the king of another realm, and so he is thrown in among the regular folk and is forced to fight his way out of this gladiatorial situation. Meanwhile, he needs to get home because there is a ticking clock on the outcome, a threat that is on his home planet of Asgard."
Cate Blanchett plays the villainous Hela, who is trying to destroy his planet. She said in an earlier interview, "I took on the role for three reasons: There has never been a female villain in the Marvel universe, she is the Goddess of Death, and it was a chance to work with (director) Taika Waititi."
The New Zealand-born actor-turned-director, Waititi (who also makes a cameo appearance), is at the helm of the third instalment of the Norse mythology, following Thor (2011) and Thor: The Dark World (2013). Ragnarok takes a comedic turn on the very serious business of being a superhero.
Says Waititi, "Marvel said they wanted the tone to be lighter. We took a risk, and Chris was happy to do that. If he'd done the same thing over and over again, and repeated what he did in the last two movies, he may as well be on a TV show."
After playing Thor eight times (with plans to shoot another Avengers movie in 2019), it's understandable Hemsworth felt the role "becoming a bit mundane at times".
He said he was thrilled with the chance to "change it up. He's still the same character, obviously, but I really welcomed the unexpected changes."
During our interview, Hemsworth jokes around with actors and extras walking by him. Clearly a popular figure on set, he treats everyone equally, unlike many movie stars who don't want to be disturbed by cast or crew.
Hemsworth, his wife of 7 years, Elsa Pataky, and their three genetically-blessed children: India Rose, 5, and twins Tristan and Sasha, 3, moved back to Australia two years ago. Life must be very different now as a multimillion-dollar star than what it was for the actor who left Melbourne in 2007.
"On Home and Away I was used to walking down the street and being recognised, but that was different because you were in people's living rooms every day on TV. So it was a little more ownership from people who were grabbing you by the arm and saying, 'Come do this photo,'" he laughs.
"It wasn't offensive, it was just familiarity. And I think it's great. Part of the reason I came back here is that people are fans of what you have done and they appreciate it and love it, but there's not that obsessiveness that there is in other parts of the world. I feel there's a sense of, 'Hey, I am proud of you for having gone and done it, and also choosing to be back here.' I've noticed that people respect that."
Now living in Byron Bay, he says, "I am originally from Melbourne, as you know, and which I love, but I have got to say that the weather up here suits me a little better."
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