POW! Superhero films knock 'em dead in China

In "Thor: The Dark World," the titular hero does battle from London to Asgard. But perhaps Thor's greatest feat will be conquering China.

Just two years ago, superhero movies—including 2011's original "Thor"—underperformed other Hollywood genres in China. But in a short period, they've emerged as a force to be reckoned with. Chinese audiences have recently clocked the most ticket sales outside the U.S. for "Iron Man 3," "Man of Steel" and "The Wolverine" this year.

Keeping up the momentum in China is surely on the minds of executives at Walt Disney, owner of Marvel, and Warner Bros., which produces DC Comics movies. China is now the second-largest market for Hollywood films, and it's only growing. Ticket sales in the first nine months of 2013 are up 35 percent over last year, said Mike Ellis, head of the Motion Picture Association of America's Asia office.

"Overall the market's going great," said Ellis. "Studios are fully committed to getting the best films in the marketplace that they can."

Big budget and special effects spectaculars like the "Fast and Furious" and "Transformers" franchises do well in China. This is, in part, because the emphasis is not on dialogue and characterization, according to Rob Cain, president of consulting and production company Pacific Bridge Pictures. Superhero films may fit the bill, but they were an unknown in China a few years ago.

"The superhero was not very familiar and not terribly popular," said Cain. "I think it's caught on pretty nicely."

This year, "Iron Man 3, Man of Steel" and "The Wolverine" all made about 10 percent of their global revenues in China, according to Box Office Mojo data. Just two years ago, superhero movies underperformed in China by this measure.

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The first "Thor" film took in just 3.2 percent of its global box office in China, and "Captain America: The First Avenger" earned just 3.8 percent of its total sales there, according to analysis by Cain. That year, the top 10 movies in China made between 7.7 and 15.4 percent of their money in the country.

Still, lightning could strike this time for the god of thunder. "Thor: The Dark World" shares a release date this weekend in China with the U.S. debut, which will help thwart bootleggers. And it faces little competition. It opens in China during a window between Russian export "Stalingrad" and Hollywood heavyweights "The Hunger Games: Catching Fire" and "Gravity." "Thor: The Dark World" opened earlier in other countries and had done about $109 million in box office sales as of Nov. 3.

"Disney is doing a good job of getting their films into the marketplace. They seem to be doing pretty well with release dates," said Cain.

A good release is a harder feat these days as more foreign films screen in China. Last year, film authorities increased the number of foreign movies eligible for revenue sharing from 20 to 34. Under the revenue-sharing model, Hollywood studios get 25 percent of their movies' Chinese ticket sales.

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Big budget blockbusters like "Thor: The Dark World" in particular stand to benefit because all 14 of the new slots are reserved for 3-D and IMAX movies.

Release dates count in China because films typically run for just two or three weeks in IMAX, and Chinese audiences pack theaters to see them, said Cain. Those opening weeks can be lucrative. The cost of an IMAX ticket in China is roughly $13, equivalent to U.S. prices outside of big cities.

Though superhero films have been nearly bulletproof in China the last two years, a crowded release can be like kryptonite.

Last August, the state-operated China Film Group Corp., the sole distributor in China, released "The Dark Knight Rises" and "The Amazing Spider-Man" during the same weekend. Theaters in China could show both films, but IMAX had to divvy up screen time.

"I think they found out that wasn't the optimal way to do it," said IMAX CEO Richard Gelfond. "It was an experiment and I think we didn't maximize revenues because of the screen sharing in those particular films." IMAX operates 152 theaters in China, with plans to build another 172. And the company recently announced a joint venture to sell $250,000 home theaters catering to the rich in China.

Despite being double-booked, the films performed in the long run. "The Amazing Spider-Man" had its best showing outside the U.S. in China, and "The Dark Knight Rises" did better in no other foreign market except the United Kingdom.

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How well "Thor: The Dark World" performs in China will provide some guidance on the future of the Marvel franchise after the spectacular success of "The Avengers." Iron Man struck gold in China with its third installment, and Gelfond's team in Asia is upbeat about Thor's next outing.

"Over the last few years, there has been a greater interest from Chinese audiences in these superhero films," said Gelfond. "We're feeling pretty good about how it's going to do."

—By CNBC's Tom DiChristopher. Follow him on Twitter @tdichristopher.