Before I go on and on about how Valerian and the City of a Thousand Planets is such a  good example of the transporting cinematic power of unbridled spectacle, so profoundly, importantly great at creating a brand new world for our eyeballs to soak up and our brains to play in, that it almost completely compensates for how entirely dumb the script is, and a massively crippling bit of casting, I should point something out to the reader. That something is that I didn't merely like, but full-on loved Jupiter Ascending, which of course means that my taste in space operas is suspicious at best, completely deranged at worst. Also, I just got finished declaring that Valerian director Luc Besson's The Fifth Element is my favorite summer movie of the 1990s. So you might say that I am heavily biased in Valerian's favor, in addition to having lost my goddamn mind altogether.

Even so, I can admit that it's not nearly as complete and magnificent an achievement as The Fifth Element; it lacks, among other things, the critical ingredient of a firm tether to our world and the lived experience of human beings in the form of a great central character like Bruce Willis in that film. Instead, Valerian has to do with Dane DeHaan and Cara Delevingne as agents Valerian and Laureline of the human space police force in the 28th Century (ignore the title: this is an extremely well-balanced two-lead film, befitting its source material). Delevingne, at least, is no worse than Besson's screenplay can stand: she has a tendency towards the most obvious line readings and sarcastic expressions, but she's perfectly satisfactory at the level of a psychologically essentialised popcorn movie character.

But DeHaan is a baffling unforced error on Besson's part. I like the actor, quite a hell of a lot in fact, and have been rooting for him ever since Chronicle, but I'm not sure how one could argue that Valerian is better off for his presence. The character of Valerian, both as originated in the comic series written by Pierre Christin and illustrated by Jean-Claude Mézières from 1967-2010 and as implied by Besson's own script, is a cocksure he-man type, effortlessly gorgeous and physically fit, charismatic enough to overcome his off-putting arrogance. DeHaan is a reedy, pale figure with permanent bags under watery eyes that make it seem like he's either about to start crying or just finished; he strikes me, and I mean this with love, as a wiry heroin addict on the cusp of withdrawals. It's possible to imagine an action hero role tailored to his specific physicality, but Valerian is absolutely not that role, and regardless of how well DeHaan plays the part from a technical standpoint - well enough, in fact, though he's not able to figure out a way to make Valerian's constant flirtation with Laureline play as dashing and charming rather than pathetic and/or creepy - there's not much salvaging a character who looks so wrong. Certainly not in a movie as wholly driven by its visuals as this one.

It's not a little thing - in a film so attenuated to surface pleasures, an appropriately swashbuckling, roguish lead is one of the big draws, and the absence of such a lead creates a powerful vacuum - but it is, kind of, the only flaw to speak of in the movie. I say "kind of" because the script is largely ineffectual and hopeless, though Valerian is very much the sort of film where the script is more a pretext than a foundation; it is, though awfully dumb. Not the fun, flighty, energetic dumb of a great space adventure; the leaden dumb of a movie that supposes itself to be smart. Or at least philosophically mindful - it is a French movie, no matter how Big Loud Hollywood the vibe is, and this leads to several conversations about the nature of love that just aren't doing it. The biggest problem with the writing, I think, is that Besson seems convinced that it's more difficult and complicated than it actually is (a military coverup that's foreshadowed so heavily, so early, that I was a little shocked to realise later on that it was meant to be something of a twist; the heroes have to navigate around several red herrings on the way to putting away the bad guys; a race of peaceful nature-loving aliens; it is, all told, nothing but thoroughly boilerplate space opera stuff), leading to some very unyielding dialogue that tries to over-enunciate the plot and themes, and always seems to end up in the mouths of the worst actors. Does Clive Owen ever have to deal with an exposition dump, something he could handle falling out of bed? Nope. Does stilted non-actor Rihanna have to wordily synopsise huge chunks of the movie's message? She sure does!

But as an actual story, the film has the goods, though the degree to which that's true almost certainly hinges in great part on the individual viewer's pre-existing sympathy for pulp sci-fi of the '60s and '70s. The film's narrative is as much about world-building as about laying out a conflict, stakes, and a clear line of action. But such world-building! The titular city is a giant constellation of spacefaring vessels that have accumulated over the last 800 years, starting around the nucleus of a space station orbiting our very own Earth in the late 20th Century (the montage sketching out its evolution over the centuries, set to Bowie's "Space Odyssey" and built around a motif of handshakes delivered by young men who grow into old men, left me feeling as happy as anything I've seen in a movie theater in 2017; it's a terrific case study in storytelling through repetitions and variations), collecting hundreds and hundreds of spacefaring civilisations in one place. Besson - aided by both the original comic arc from which this film's story is derived (1975's "Ambassador of the Shadows"), and by a sizable collection of concept artists, above and beyond the work of production designer Hugues Tissandier - has a hell of a time moving the story around this polyglot of alien microcosms, allow for some delightfully old-school sci-fi concepts, including an amorphous blob shape changer who just wants to be loved, and a dinner banquet with human-loving aliens. It's an old-fashioned adventure that plainly bears the traces of Besson's adolescent fascination with the comic, for good and bad: other than the gorgeous, expensive CGI used to bring the world to live, there's nothing in Valerian that feels like it has paid any attention to the last 40 years.

It at least means that the film is quite a rare bird; the very opening, set on a beachfront alien landscape that looks like a prog rock album cover, already demonstrates that we're going to be in a place that modern blockbuster cinema has limited interested in exploring (though if the Marvel films keep up the Jack Kirby love affair that Guardians of the Galaxy, Vol. 2 suggested, this will hopefully change), and that's not even the loopiest dreamscape the film presents. In short order, we'll be in a desert where the clouds float by like rust-and-teal cotton candy.

As far as presenting elaborately garish spectacle, then, the film is an absolute triumph. The first half includes some giddily inventive action setpieces, exactly the kind of thing that a bright 12-year-old geek might have dreamed up back in the early '70s. One early chase involves Valerian looking into one dimension as he walks through another, with Laureline barking out directions, and the dazzling brio with which the POV dissolves and wipes from one dimension to the other is the best kind of dizzying movie magic. It's showing off, clearly, but showing off things that are delightful as can be, and if not entirely unprecedented (it's similar to the "car chase in two time periods" scene from Tony Scott's Déjà Vu, though considerably more complicated and busy), it's still a dazzling display of choreographic flair. Similarly, there's a long-take chase later in the film, following Valerian through several different biomes, as he plunges through three-dimensional space folding in on itself. It's thrilling both for the elaborate design and complexity of the movement, and for the simple recognition that in space, movement doesn't have to be on flat planes, a truth that frequently seems to escape the creators of space movies and television.

If this all lacks the heart and soul of The Fifth Element, as well as the flagrant Gallic eccentricity of that film, that's an undeniable disappointment. So is the rather bleak relationship between Laureline (a strong-willed and driven character well-fitted within Delevingne's limitations) and Valerian (a wash-out), the emotional center of the film coming across as uncomfortable and forced - if the film was willing to let Valerian come across as a hapless creep, it might have been able to do something, but it seems to genuinely want him to be a romantic lead, and that dog just don't hunt. My hope for Valerian was the best popcorn film of the summer; it wasn't even the second-best popcorn film of July. Still, it's a spectacle par excellence, and a sumptuous display of inventive sci-fi action direction, and choreography within impossible spaces. It has staggeringly beautiful design and a sublimely boisterous Alexandre Desplat score, and several perfect little jewels of performance hiding inside. It's a genuinely transporting film fantasy, unafraid to let its ambitions race beyond its abilities, and its colossal failure to connect with any audience whatsoever strikes me as one of the worst cinematic tragedies of the season.