They are waiting for Thor. It’s a few days before the U.S. premiere of The Avengers, which will zoom to a staggering $200 million opening weekend, and outside a downtown New York hotel, fans cluster, hoping for an autograph, an iPhone pic, a glimpse of the brawny 28-year-old Australian actor. He is Chris Hemsworth, not yet a household name but a confident bet to be one—still new enough to movies that he’s not weary of this fuss or the global promotional haul that has shipped him and his blond ­ponytail from Los Angeles to France to Russia, then Germany and Italy and En­gland before, finally, Manhattan.

“It’s easy to go, ‘Oh, I’m just talking about the same questions’ or ‘I’m exhausted from traveling’—but no, no,” Hemsworth says, sitting in the hotel’s library. “I would much rather be doing this than things I have done in the past. It’s an incredibly exciting job.”

He is not jaded. This madness is fun. How can it not be? A former teenage surfer and the older brother of Hunger Games phenom Liam Hemsworth, Chris is riding one of Hollywood’s great franchises—The Avengers is a smash, as was Thor; and Thor 2 is in the works. (At this rate, Hemsworth could be swinging that hammer into middle age.) He’s also in theaters right now, with Snow White and the Huntsman. Next comes the seventies auto-racing drama Rush, directed by Ron Howard, in which Hemsworth plays the late real-life driver James Hunt, a charming roué remembered as much for his bedroom conquests as for his triumphs on the track. “Ron keeps saying it was when ‘the driving was dangerous and the sex was safe,’ ” Hemsworth says, laughing. “Now it’s the other way around.”

The actor talks excitedly of learning to drive an open-wheel race car and the nerve-racking challenge of playing a complicated, ­addictive character like Hunt. And then there’s fatherhood; last month, Hemsworth’s wife, Elsa Pataky, gave birth to their first child. “My older brother said to me, ‘It’s not about you anymore,’ ” Hemsworth says. “What a great thing it is to be slapped into that reality. You have purpose and focus.”

It all feels nervously fresh, exhilarating, hopeful. The actor excuses himself and steps outside to the waiting throng of Thor obsessives. Everyone gets a picture; every poster gets a signature. Then he climbs into a waiting SUV—done for now but really just getting started.