It is well to avoid making absolute statements, especially absolute statements about weirdly idiosyncratic and fundamentally unquantifiable things, but I'm feeling feisty. So here goes: I think it's entirely likely that the most interesting and important thing happening to cinema anywhere in the world right now is the Chinese film industry's attempts - largely successful - to replicate the genres and production values of Hollywood popcorn movies, while completely overhauling their thematic and tonal preoccupations. And The Wandering Earth - a massive box office hit in its native country that is being widely sold (outside of China, anyway) as the first Chinese sci-fi epic - is maybe the most interesting product of the Chinese industry in this particular mode. Does this necessarily mean that The Wandering Earth is the most interesting motion picture of the late 2010s? I will put it this way: it's not obviously not that thing.

"Interesting", I should hasten to point out, is not inherently the same thing as "good". The Wandering Earth is a magnificently fascinating object, and it's also a movie that, to be blunt about it, I didn't much enjoy watching. It's 125 minutes and feels close to half-again that long; this is largely because it has four different climaxes in its second half. It starts out by minutely explaining all the details of how its fantastical science works, but ends in an explosion of technobabble as we watch giant machines with no obvious function are manipulated by screaming people as the clock ticks down. It keeps switching back and forth between a hugely conventional, American-style tale of an estranged father and son, and an ensemble-based thriller in which collective action rather than individual heroism carries the day, and this contrast is just really damn tiresome to keep track of. It's a mess, basically, exactly what you should expect when a team of seven screenwriters, including director Gwo Frant transform a hard sci-fi novella (by Liu Cixin) into a melodrama with a substantially different plot.

But, in its way, a pretty compelling, exciting mess. The hook is pure high-concept heaven, so fearlessly ridiculous that you can't not love it. Sometime in the not enormously far future, Earth scientists have discovered that our sun is starting to go wrong, and will shortly send out enormous flares that will destroy the planet. The solution is as straightforward as it is demented: consolidate all the resources of human civilization into one massive project to strap a whole fuckload of city-sized rockets to one-half of Earth, and fly it to the nearest star system. This trip will take some 2500 years, so all of humanity is obliged to reorganise itself: after some half of all people are wiped out in the massive flooding that is triggered by the launch out of orbit, the remaining few billion souls now live in underground bunkers, shielded against the extreme low temperatures that have frozen the entire outer surface of the globe. A few doughty specimens work as drivers and technicians on the surface, and an even smaller number live on the spaceship orbiting Earth that serves as control room and navigation center for the trip.

This is all the backstory. The story is that, 17 years into the flight, Earth has gotten a smidgen too close to Jupiter, and is about to plummet into the gas giant, there to be crushed into rocky pulp. "High concept" doesn't even begin to describe it.

Against this backdrop is a tidy family drama: Liu Peiqiang (Wu Jing) was one of the first men to travel to the space station, and his 18-year mission is just about up, meaning that he can at last return to his now-grown son Qi (Qu Chuxiao). Except that Qi has grown immensely resentful of his father. These days, he's being an ill-tempered young hothead, causing much misery for his truck-driver grandfather Han Ziang (Ng Man-tat), and roping his adopted sister Duoduo (Zhao Jinmai) into various dangerous schemes. The latest of these puts both of them, along with Ziang, in a prison near the surface, where they meet Australian-Chinese comic relief Tim (Mike Sui). And he'll be the first of many individuals, some seasoned pros and some helpless neophytes, who cross paths with our heroes as they form a team to make a last-ditch attempt to keep the Earth from becoming a blip in the Great Red Spot. And then a last-ditch attempt after that. And still a third one after that.

It feels very much like an American disaster movie of the '90s, with some culturally specific tweaks (most obviously the lack of anything even hinting at a romantic subplot, though the focus on teamwork is pretty obvious as well), and of course a whole mess of '10s CGI to make all of the impossibilities (the Earth flying like a jet, massive frozen landscapes that used to be great cities, rocket engines towering like Elder Gods in the wastes) come to life. The effects work, at least, is quite extravagant: it's the sort of thing where so much of it is so obviously fantastic that it seems unconvincing, until you step back to realise just how much of the film actually exists inside a computer, and all those unfathomably large expanses of ice and ruin assert themselves as some unusually effective world-building. Probably the best thing The Wandering Earth has over its U.S. counterparts is its sense of vastness: the land stretching out endless for what feels like hundreds of miles, and also the looming presence of Jupiter, almost totally filling the night sky like some sprawling, swirling oil painting from hell. And not just visual vastness: the film's awareness of time frames, the nonchalant way that 17 years pass on a trip to Jupiter with 2483 more years to go, knocks the usual sci-fi "get there and back in what feels like an afternoon" right off its perch. The film does a superb job of communicating the exhaustion of space travel, and the pent-up claustrophobia that would naturally attend to living in underground metropolises that, no matter how much stuff is in them, still have close walls and low ceilings. It is a very looming film, very weighty, but never so much so that it loses its sense of swashbuckling fun and racing against time.

The setting is so damn good that part of me wonders if I actually didn't enjoy this after all; but God, is it a meandering, sludgy bit of storytelling. It's a bit tricky keeping all of the characters in order, given that we're introduced to them in large batches and almost all of them are wearing indistinguishable sci-fi cold weather gear; then again, the dissolution of individuals into a huge team is somewhat the film's point. It's all about collective actions: of several people to solve problems, of several nations to save humanity. It supposes, quite without making a big deal about it, that the little petty things that divide us into smaller and smaller tribes would be ignored more or less on the spot in the face of world-ending crisis, and celebrates the ability of mass effort to do literally unbelievable things. So perhaps the fact that the cast eventually turns into "Qi, Duoduo, the Australian goofball, and the other dozen people" isn't a flaw.

But flaw or not, it also isn't much fun to watch, and it only gets less fun as the movie keeps throwing up obstacles more or less at random. It basically turns into an endless chain of problem-solving exercises, most of them looking awfully similar: Gwo can't do very much with all the unchanging ice and doesn't do much more with the raging inferno of the engine area that's the film's only particularly distinct location. If the film is, in the abstract, deeply interesting (watching as the film repurposes and transmogrifies stock narrative situations for themes very different than the ones they were designed to espouse), in the details, it is barely interesting at all. So that's kind of a neat tension in and of itself, but one that doesn't make for a hugely rewarding night out. The film's dazzling, and big, and genuinely epic in its concerns and portent; but frankly, it's also kind of a chore to get through.