Judging by his box-office figures, Thor (Chris Hemsworth) is one of the least popular of Marvel’s cinematic superheroes. It’s all relative, of course. The God of Thunder’s first two films made around $200 million (£152 million) each, so they’re not what you’d call flops. But compared to his buddies in the Avengers, Thor has never quite taken flight. And even in his own vehicles, he is in constant danger of being upstaged by his own brother and smarmy arch-enemy, Loki (Tom Hiddleston).

Thor: Ragnarok should change all that. Undoubtedly the best of the character’s three films, it’s more confident than the others, more kaleidoscopically colourful, and more eye-catching in its design. It has more coherent fight sequences and more impressive digital effects than its predecessors did. And while it takes its hero’s story to surprising new places, it has an endearing reverence for his comic-book roots: he keeps calling himself “The Mighty Thor”, because that used to be the title of his monthly comic.

lt presents us with the comforting notion that outer space isn’t all that different from a glam rock-themed disco

More importantly, this sequel, or threequel, establishes its blond leading man as somebody who’s fun to hang around with for two hours. Not for him the geopolitical debates or the personal angst of Iron Man and Captain America. This time around, Thor is a hearty lunk who is swaggeringly sure of how heroic he is, even if he keeps bumping into things and knocking them over. Whenever he makes a speech about the importance of his noble mission, you can be pretty sure he is going to be hit on the head moments later - and Hemsworth is just as willing to be a stooge in this film as he was in last year’s Ghostbusters remake. The credit for the knockabout tone should probably go to the director, Taika Waititi, a New Zealand comedy specialist who made the sublime vampire mock-doc, What We Do in the Shadows. In his hands, Thor: Ragnarok is so knowingly daft that it almost qualifies as a parody. 

Norse to meet you

In fact, it has less in common with the previous Thor outings than it does with the Guardians of the Galaxy films. Like them, it’s a light-hearted intergalactic romp full of aliens of all shapes and sizes - the director himself appears as a mild-mannered rock-skinned giant. And like Guardians of the Galaxy, it presents us with the comforting notion that outer space isn’t all that different from a glam rock-themed disco. A few scenes near the beginning are set on Earth, because Thor and Loki drop in on Doctor Strange (Benedict Cumberbatch). But afterwards the action hops so easily from planet to planet that watching the film feels pleasingly like flicking through a pile of comics. Nor is there any sign of Thor’s ex-girlfriend Jane (Natalie Portman) or the other earthlings from his original supporting cast. Liberated from those mere mortals and their everyday concerns, the film derives much of its humour from the idea that the cape-wearing, mallet-swinging Norse deity is more ordinary, and certainly more conservatively dressed, than the weirdos he meets on his travels.

If Loki has been the most memorable villain in Marvel’s canon so far, Hela at last gives him some competition

It’s not all fun and games, though. Thor’s father Odin (Anthony Hopkins) has gone missing, and his utopian homeworld of Asgard is conquered by Hela (Cate Blanchett), the strutting Goddess of Death. She isn’t the most complex of baddies, but she looks fabulous in her range of black catsuits and her chandelier-shaped headgear, and Blanchett relishes playing her as a bored, drawling, English aristocrat. If Loki has been the most memorable villain in Marvel’s canon so far, Hela at last gives him some competition.

It’s up to Thor to save the kingdom, of course. But he is stranded on a distant planet ruled by an omnipotent dandy known as The Grandmaster. Played by Jeff Goldblum with all of his quizzical, hesitant Jeff Goldblum-ishness, and sporting a golden wizard’s outfit that would have been rejected as being over-the-top by Elton John in the 1970s, The Grandmaster forces Thor to take part in a brutal gladiatorial contest, but the thunder god runs into two people who might just help him get back to Asgard: a mysterious warrior (Tessa Thompson) with a link to his past, and his old pal the Hulk (Mark Ruffalo).

Thor: Ragnarok is the wittiest and most straightforwardly enjoyable of Marvel’s blockbusters. The screenplay, by Eric Pearson, Craig Kyle, and Christopher Yost, gives each of the characters something worthwhile to do and something amusing to say, and when its various strands are tied together in time for the momentous finale, even the most superhero-wary viewers will have smiles on their faces. 

The only snag is that it’s all so bubbly and inconsequential that it can feel as if you’re watching a hugely expensive sitcom episode. For much of the running time, the heroes are bantering and squabbling on the Grandmaster’s glittery planet, and they seem to be light years away - emotionally as well as geographically - from anything that’s happening on Asgard, let alone on Earth. In theory, the fate of the universe is at stake. In practice, you’ll care more about Thor’s new haircut than Hela’s reign of terror.

Part of the problem is that Thor: Ragnarok is too familiar to be truly thrilling. It may seem like an odd thing to say about a psychedelic sci-fi comedy in which a Viking god wrestles monsters in a coliseum on the far side of the cosmos, but it serves up a lot of what you’d expect from Marvel: aliens, uneasy allies, cities being levelled by a vastly powerful villain, and so on. Perhaps the trouble is that the superhero trend is finally running out of steam. But if Thor: Ragnarok is anything to go by, at least it will be fun while it lasts.

★★★★☆ 

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