As the Chinese box office sagged alarmingly for an entire year, from July 2016 to June 2017, filmmakers and studios in the Middle Kingdom began desperately searching for answers. Many concluded that bigger Chinese properties were the solution and banked on new, higher-quality franchises coming on stream in 2018.

No one was paying much attention to “Wolf Warrior II.” They are now.

Since its July 27 debut in China, the action thriller has confounded expectations to become a box office stunner. In less than two days, it surpassed the $88 million scored by the franchise’s first installment in 2015. Ten days later, it overtook last year’s sensation, “The Mermaid,” as China’s top-grossing film of all time. Now, its $810 million take after just five weekends has made “Wolf Warrior II” the second-highest-earning title in a single territory in history, behind “Star Wars: The Force Awakens” in North America.

In the process, it has sparked rethinking in both China and Hollywood over how best to approach and exploit the Chinese movie market, which is on track to become the world’s largest in the next few years. “Wolf Warrior II” shows just what a well-crafted Chinese film — made with some foreign help — can do.

The movie features a muscular, adrenaline-fueled story whose unstoppable hero is a former member of a fictitious Chinese special ops unit called the Wolf Warriors. The action takes place in an unnamed African country where China has built hospitals and provided factory jobs for the locals; the bad guys are revolutionaries and Western mercenaries. (If the politics sound jarring, just swap the nationalities.)

Chinese audiences have responded strongly to the film’s patriotism and to the relentless action provided by former martial arts star Wu Jing as both director and protagonist.

“China has found its ‘Rambo.’ This is definitely an important event.” Rance Pow, Artisan Gateway

“It is a feel-good story for the Chinese population. The hero is a military guy, and the message is that he treats everyone equally. It is very modern, there’s a touch of comedy, and some 30% is spoken in English,” says Jeff Yip, business development director at The H Collective, a new U.S.-Chinese production and distribution firm. The company owns the rights to “Wolf Warrior II” for North America, where the film has made more than $2.3 million. A gross of $1 million is considered a hit for a Chinese movie Stateside, but the unparalleled performance of “Wolf Warrior II” in China has piqued greater interest. An Imax conversion that bowed Aug. 25 was given a limited outing in the U.S.

The movie isn’t the product of one of China’s mega-studios, such as Huayi, Bona, Enlight or China Film Group, though Wanda owns a small piece. Rather, it was conceived and controlled by Beijing Century and by Wu, who started planning a sequel immediately after the first film, made for $5 million, hit pay dirt.

Hollywood talent has contributed significantly to the second film. Increasing the budget to $30 million allowed Wu to bring in Joe and Anthony Russo as consultants and to pay for better production values. With the Russos came stunt director Sam Hargrave (“Captain America: Civil War”), composer Joseph Trapanese (“Tron: Legacy”) and a largely foreign sound unit. American actor Frank Grillo stars alongside Wu.

The early signs weren’t promising. In May, a trailer launch was criticized for seemingly borrowing footage from “X-Men: First Class.” Even the film’s July 27 opening date seemed questionable, since it clashed directly with the government-backed propaganda movie “The Founding of an Army,” from director Andrew Lau. With the nationalistic plot of “Wolf Warrior II,” the two films seemed to appeal to the same constituency.

But “Wolf Warrior II” has left “The Founding of an Army” in the dust, showing that support from the Chinese government isn’t everything. “What really worked for ‘Wolf Warrior II’ was combining the best elements of action and international stars in service of something enjoyable to Chinese audiences,” says Yip.

The film was no doubt helped by being released during the summer blackout period, when major foreign movies are banned from domestic release. But that’s only part of the equation.

“The filmmakers worked really hard to make this a quality production,” says Jane Shao, co-founder of exhibition chain Lumiere Pavilions. “At base, this is a hero movie no different from a Western or a Jackie Chan or Jet Li martial arts movie of old.”

For Hollywood, the lesson is that its obsession with China’s quota on imported films, now the subject of a new round of talks by U.S. and Chinese negotiators, is potentially shortsighted. Instead, Hollywood studios looking to bolster their bottom lines might want to redouble efforts to back local filmmakers in China and invest in high-quality local content, not just in their own tentpoles.

“China has found its ‘Rambo.’ We expect more movies in this space,” says Rance Pow, founder/CEO of consultancy Artisan Gateway. “This is definitely an important event.”

Always trying to make films that work in both the U.S. and China might be a futile exercise. Many variations on the theme have been tried: overblown co-productions; Hollywood films that try to cater to Chinese tastes but still get it wrong; Chinese pictures that wrongly assume that the casting of a Western star will translate into overseas sales.

The astounding box office performance of “Wolf Warrior II” suggests that in a country of 1.3 billion people, succeeding on home turf alone can be more than enough.