Dismythed: "Thor"

I couldn't tell you why exactly, but - even after spotting the poster credit "with Anthony Hopkins as Odin" - my expectations going into Thor were low to non-existent, and they dimmed only further on being handed a pair of 3D spectacles at the cinema doors. Once again, a major studio invites us into a (here, especially) murky world engineered specifically to extort money from cinemagoers already struggling to make the price of tickets and popcorn. Still, if there's any good news here, it's that the film gets its weakest material out of the way in the opening half-hour - the time traditionally alloted to the directors and screenwriters of comic-book movies to squeeze several dozen issues' worth of backstory into an appreciable shape.

The gods in Thor live in an Asgard made up of remaindered Star Trek sets that collectively manage to be only around 14% more convincing than the locations of last year's Clash of the Titans remake. In a palace that looks uncannily like a set of organ pipes acquired at a church charity sale, the arrogant and headstrong pretender to the throne Thor (Chris Hemsworth; nope, me neither) crosses his father (Hopkins) by entering enthusiastically into the kind of pitched combat summer movies like this have to whip up on a regular basis just to survive in the marketplace. Odin banishes Thor to the realm of mortals, then - heartbroken - keels over, clutching his chest.

Spotting a power vacuum emerging, Thor's brother Loki (Tom Hiddleston) - black of hair, deceptively sensitive of demeanour - assumes the throne, but he's been touched by the cold, dead hands of the Frost Giants, malevolent forces who sweep in like the what-d'ya-ma-call-'em from the Harry Potter movies andzzzzzzzzzzzzzzzzzzzzzzz. In fairness, Thor starts to warm up a little once the title character winds up in New Mexico, where he's adopted by a scientific research team headed up by Jane Foster (Natalie Portman). These scenes, at least, can toss us some of the fish-out-of-water comedy rehearsed in such films as Crocodile Dundee and California Man, a pair of works the genial midsection comes indirectly to channel: setting out to retrieve the hammer he's been separated from on his journey to Earth, our burly hero swaggers into a small-town pet store and bellows, to the bemusement of the humble clerk working therein, "I need a horse!"

The film has been conceived to tesselate with existing and future franchises across the Marvel range, so non-nerds shouldn't be surprised if some of the references pass them by. Clark Gregg offers a good-natured reprise of his security agent Coulson, from the Iron Man films; there's a cameo for The Hurt Locker's Jeremy Renner as a character referred to as Archer, who'll presumably feature in a spin-off of his own at some point in the near-future; and, as in Iron Man, there's a set-up scene at the very end of the end credits featuring Samuel L. Jackson in an eyepatch, and you wonder whether the actor is happy that his most prominent filmwork in years is playing out long after everybody's made their way out to the car park.

What Thor lacks is an anchoring central performance. Iron Man had Downey Jr., whose hybrid of charm and corporate calculation was crucial to what those movies were; Hemsworth, by contrast, is a rugby club captain angling for Heath Ledger replacement duties, so it's perhaps apt he should end up brawling in the mud with one foe, like a common-or-garden prop forward. Elsewhere, the acting isn't bad. Kenneth Branagh was a surprise pick to direct this material, yet - given his long-standing interest in myths of the Frankenstein variety - not an inexplicable one: he stages the business of the gods as repertory Shakespeare, with a lot of very formal declaiming in stiff tableaux, but Portman, Stellan Skarsgard and Kat Dennings make a tight, well-rehearsed unit as the scientists, and Hiddleston (Unrelated, Archipelago) makes for interesting, leftfield casting, showing an admirable willingness to underplay Loki's villainy, even if the subtlety of the actor's choices was always likely to get dwarfed by this scale of production.

It's far from a disaster, then, but hardly distinctive in its field; devoid of Iron Man's unpredictable pop energy, the film assumes some altogether square proportions, displaying no real or novel idea how to get the kids in, save to make a $150m effects movie based on a comic book. At one crucial point, Dennings' Darcy - here chiefly to facilitate the now-obligatory Facebook namedrop - has her iPod seized by Coulson's security forces, and if the script had told us what was on the device ("I can't believe the Pentagon is jonesing for My Chemical Romance," say), I'd have had more time for Thor as a proposition; as it is, the reference to the brand name is assumed in itself to be enough.

What's left behind is more bullshit propaganda for the alpha-male cause, positing that every grunting, long-haired aggromonger is just waiting for the right girl to school them in the appropriate etiquette. Sure enough, after a night spent around the campfire with Portman's scientist, Thor is observed putting down the hammer in favour of picking up the whisk, whipping up some scrambled eggs with a boyish smile: me Thor, you Jane. The delicacy and sensitivity with which Sam Raimi handled Peter Parker's transformation into Spider-Man is nowhere to be seen; in a film dealing in blunt, brute opening-weekend force, Hemsworth is granted a two-minute display of shirtlessness that causes even the generally sensible Darcy to swoon "for a crazy homeless person, he's really cut". Our heroes once had journeys to go on before they could consider laying siege to a fair maiden's heart; now they drop from the sky looking for all the world like seven-times champions of the mixed martial arts.

Thor is on nationwide release.