Still, it’s a sizable gamble considering the potential pitfalls. There is no guarantee that moviegoers will embrace the “Hobbit” films with the same fervor as the “Rings” trilogy. Those films had combined worldwide ticket sales of about $3 billion (in 2012 dollars, after adjusting for inflation). Warner and its New Line Cinema unit, both of which declined to comment for this article, have high hopes for the movies, which also have backing from MGM.

Other big questions remain, starting with Mr. Jackson’s decision to shoot the films at 48 frames a second, twice the usual rate, in search of new visual heights; early reaction to the result has been sharply mixed. Then there is the capricious nature of the filmmaking business, which has become increasingly mobile and will quickly flee to the national or local government offering the best incentives.

Exchange rates play a sizable part in the bidding process. Favorable rates were one reason Mr. Jackson and his partners were able to build New Zealand into a crossroads for special effects and postproduction work, the kind of business that George Lucas once cornered in Northern California. “Avatar,” “Marvel’s The Avengers,” “The Adventures of Tintin” and “Prometheus” are among the many films that have crossed through Mr. Jackson’s Wellington-based effects shop, Weta Digital, on their way to theaters.

But recently a stronger New Zealand dollar, which currently trades for about 82 cents in United States currency, has eroded its cost advantage for North American companies, something that other countries are trying to exploit. Northern Ireland now claims to be the “new New Zealand,” while Serbia says it is “New Zealand, but cheaper,” notes Gisella Carr, the chief executive of Film New Zealand, an industry group that scours the globe for film work.

Hollywood is also looking to China, where an aggressive government and its allied companies are building expensive movie facilities and offering access to a vast market in exchange for a stake in American studio pictures.

New Zealand does have language in its favor, since the crews speak English. It also has a “just do it” approach that endears it to studios. “We’re not afraid,” said Tim Coddington, an Auckland-based producer who worked on the “Chronicles of Narnia” fantasies in New Zealand. Still, for Mr. Key and others, the primary challenge remains linked tightly to Mr. Jackson: how do you build a significant and enduring economic sector from a local business dominated by one man?

“Peter Jackson might make movies for the next 50 years, or he might not,” said Mr. Key. “You can’t base an industry solely on one person. That’s a very vulnerable business strategy.”