But Hemsworth understands that box-office success requires a measure of disclosure, a certain tithing of the private self to the nosy moviegoing public. "The biggest thing is, you worry about being boring," he says, looking for a way to talk about himself without sounding conceited or falsely modest or unaware of the strange allure of celebrity (he is none of these things).

It's not just birthday-crashing writer types who push Hemsworth to overshare. "I worked with plenty of directors who are like, 'Yeah, but what's in there? Tell me about that time . . .' And I'm like, 'Listen, there is something in there, but I ain't gonna tell you and exploit it.' I hold that stuff pretty close. We all like the drama of the wildest personalities, but I'm not going to invent something to wallow in just to make me sound interesting."

Pressed to explain his swift rise to the top of the he-man heap, Hemsworth points to a certain bullheaded desire to win that's driven him since he was a kid, the middle of three brothers in an active, competitive family. "My dad talks about the times when we'd play backyard cricket: If I got bowled out, I'd just refuse to let go of the bat and swing it at anyone who tried to take it away from me," Hemsworth recalls. "I like to think that's been tempered a bit over the years."

When I ask Portman what she means by her compliment that Hemsworth is a "full human," she says: "He's confident in a very quiet way. Not a look-at-me kind of way. He's like the silent guy at the table. He can sit there and listen and be generous and not have to be tap-dancing all the time—which is really unusual for an actor."

And A-list directors have begun to take notice of Hemsworth's quieter side. Most immediately, there's the Michael Mann cybercrime film he's been shooting in Jakarta (and Los Angeles and Hong Kong before that). "This is a little stiller than I've been before," Hemsworth says of his role as a brainy hacker.

Later, when I'm back home, Mann will call from Malaysia, where he's two days away from finishing the exhausting shoot for his as-yet-untitled thriller. "Four countries, 71 locations, 66 days," Mann says. His message is that hiring Hemsworth as a computer genius was not casting against type: "It would be a mistake to typecast Chris in any way. He can do anything he decides he wants to do—he has that much command over his abilities and career.

"He's a real solid citizen," Mann adds, laughing. "I don't mean he's registered to vote. I mean he's there, you know? If we need to shoot something over again, he's there. He's got a great sense of responsibility and an integrity as a man that I immediately respond to and respect. He's a smart guy, and he really can do just about anything."

Hemsworth, for his part, wasn't so sure he could handle one of the things Mann asked him to do to prepare for the role. This time it wasn't learning a new martial-arts discipline. Or bulking up through overeating and overtraining. Or learning to perform against a green screen. It was worse. Much worse: nerd camp.

"I did two months of computer lessons before we started shooting," he says. "This computer teacher with a Ph.D. from UCLA would come into this little room and give me lessons in Unix commands and whatnot. It was exciting the first day or two, then I was like, 'Oh no, this is why I didn't take a desk job.' Drank more coffee than I'd ever had in my life, because it was literally putting me to sleep."

Hemsworth shakes his head under the Balinese sun in remembered disbelief. A friend ambles over to the terrace and replaces our depleted fruit plate with a couple of cold bottles of Bintang. The weekend's almost over, and it's agreed they'd better finish the cases of beer they brought in.

"I think I enjoyed sword fighting more than computer lessons," he says.

The nerd training eventually paid off. "I learned to type, for one," Hemsworth says. "I can't say I can hack into your Swiss bank account, but I can pretend to. There's an intelligence to this character that's certainly beyond my intelligence and some of the characters I've played before. They can make me smarter in the editing."

• • •

"These days, even 5-year-olds will look at something and say, 'Ah, the CGI's crap—I'm not watching this.'"

We're talking about the pitfalls of performing opposite a green screen rather than other actors. Hemsworth says he tries not to think too much about what kind of films he should be saying yes to. But once he did try a character-driven role, he thought: "Oh my God, what a relief."

That first encounter with an actory, talky, thinky role came in the form of the real-life seventies-era British Formula One champ James Hunt in Ron Howard's Rush. Channeling the persona of a shite-talking, lady-killing Alfie-on-wheels with predictably enviable hair might not seem like a stretch for the hunky Hemsworth. But beneath the engine roar, the film is a psychological study of the competitive spirit.

"Chris' high-profile performances have been so focused on the physical, the way he moved," Howard says. "But he sent me this fantastic, very raw audition tape he made in his motel room. He was wearing a T-shirt, and his hair was loose, and he had that body language. Chris is a surfer, and James Hunt exuded a kind of California quality, but with a British public-school education—"

"And great hair," I say, interrupting.

"And great hair!" Howard goes on. "He killed it in this little audition, including the accent. And the writer, Peter Morgan, and I just looked at each other and said, 'Okay, now we got Hunt.' We stopped searching. It was pretty incredible."

Howard was impressed enough with Hemsworth on set that the two are collaborating again for the director's next project, In the Heart of the Sea, which tracks the true-story misfortunes of the whale ship Essex, upon which Melville based Moby Dick.

And Howard is unequivocal about where he sees Hemsworth's post-action-hero roles propelling him: "It's a little bit like when you saw Harrison Ford as Indiana Jones and then you saw him in Witness. I think he's going to earn people's understanding and respect in those kinds of ways, and I hope that Rush is the beginning of that."

Hemsworth relished the change of pace and the new challenges. "It was incredibly satisfying to be on a much more intimate set, focused on the truth of a scene, as opposed to 'Now swing on a wire and smash the bad guy with your ax,'" he says. "The fear, the newness," Hemsworth continues, snapping his fingers excitedly, "is what keeps you on your game."