Pedro Pascal, left, and Matt Damon star in “The Great Wall.” (Jasin Boland/Universal Pictures)

“The Great Wall” arrives with a lot at stake, being the most expensive co-production ever filmed in China, and the first one to feature a bona fide movie star, in the person of Matt Damon.

The film met with early criticism for casting Damon as what many presumed would be the usual “white savior.” It turns out that his character, a mercenary soldier in an unspecified long-ago era who has come to China on the prowl for gunpowder, is less an out-and-out hero than a foil for ideas of national identity and cultural chauvinism that China is obviously eager to export for global consumption.

To buy that message, though, viewers must first buy “The Great Wall,” which, despite the hype that has surrounded it, feels like a letdown. An action drama cut from the same fantastical cloth as “The Lord of the Rings” and “Game of Thrones” — one of whose stars, Pedro Pascal, plays Damon’s wisecracking sidekick — the movie might have been epic and startlingly original, but instead plays out like a retread of every effects-heavy movie that’s been fatally over-tweaked to out-CGI “Avatar.” For every stirring set piece of disciplined Chinese warriors doing acrobatic battle while decked out in shades of crimson, purple and iridescent blue, there are repetitive shots of lizardlike monsters being speared in the gullet, their green blood spewing out like so much Kids’ Choice Awards slime.

In an opening scene reminiscent of his intergalactic sojourn in “The Martian,” Damon — who plays a scruffy bow-and-arrow-for-hire named William Garin — plods across the terra-cotta-hued North Chinese desert with his henchmen, who later are attacked by an unseen being that leaves only one scaly-toed claw behind. Along with Tovar (Pascal), William is later taken hostage by commander Lin (Jing Tian) and her general (Zhang Hanyu), who with their thousands of troops are preparing for an invasion of the Tao Tei, a breed of voraciously destructive monster that appears, every 60 years, to remind humans of the wages of untempered greed. They’re kind of like locusts, but with more scales, teeth and weird eye sockets in their shoulders.

A crack marksman, William soon allies himself with the principled and courageous Lin, despite the misgivings of Tovar and another English-speaking prisoner, played by Willem Dafoe as if he’s not only trying to get out of the tower, but out of the movie. Written by a team of American screenwriters and directed by Zhang Yimou, “The Great Wall” groans with the weight of wooden dialogue, starchy performances and a vaguely Irish brogue that Damon continually rediscovers, like a veritable lost shoe, throughout the film’s brisk running time. It might be redundant, ridiculous, monotonous and only fitfully entertaining, but it’s over blessedly quick.

Matt Damon delivers a workmanlike performance that remains grim, despite attempts at “Princess Bride”-like levity that land with a thud. (Jasin Boland/Universal Pictures)

Fans of Zhang — who directed such rich, extravagantly constructed dramas as “Raise the Red Lantern” and “House of the Flying Daggers” — will recognize little of the master’s hand in “The Great Wall,” which, despite that rainbow-hued armor and some eye-catching sets, lacks the kind of visual elegance for which he’s become rightfully revered. For Damon’s part, he delivers a stolid, workmanlike performance that remains grim despite attempts at “Princess Bride”-like levity that land with an anachronistic thud. The Chinese actors similarly hit their marks with professionalism and little else, although Ryan Zheng is undeniably appealing as a frightened guard William befriends.

But character and story aren’t what drive “The Great Wall.” It’s spectacle, which in this case involves not just the imposing titular structure, but cadres of spear-wielding female warriors, tethered to ropes, an airborne flotilla of giant white silk balloons and a climactic sequence filmed at the Imperial Palace. By then, the preposterousness of “The Great Wall” has given way to simple, sweet-natured naivete. “The Great Wall” isn’t great. It isn’t even very good. But it’s a start.

The Great Wall (103 minutes, at area theaters) is rated PG-13 for sequences of fantasy action violence. In Mandarin and English with subtitles.