LOS ANGELES — Hollywood’s global business strategy, which counts on huge ticket sales in China for high-budget fantasies in 3-D and large-screen Imax formats, is coming unhinged.

Last year, helped by a high-level deal that expanded the number of foreign films for release there, American blockbusters like “Mission: Impossible — Ghost Protocol” led the Chinese box office for 23 straight weeks, and received a disproportionately large share of their ticket sales from China.

More big releases were on the way, and the floodgates in the world’s second-largest film market appeared ready to swing open.

But something unexpected happened on the way to the bank: demand tapered off sharply.

In the first quarter this year, ticket sales for American movies in China — including films as prominent as “The Hobbit: An Unexpected Journey” and “Skyfall” — fell 65 percent, to about $200 million, while sales for Chinese-language films rose 128 percent, to well over $500 million, according to the online publication Chinafilmbiz.com.