When the movie studios run out of superheroes who everybody knows, they will have to chance their arm with the ones only hardcore comic book aficionados care about.

So here we are with Thor, the Marvel superhero who wasn't really a superhero but a Nordic God of Thunder, exiled on earth and flying around in a red cape protecting humans. If Iron Man is Marvel's Batman, Thor is Superman with his big hammer.

Since Marvel took control over the film adaptations of their creations, they have tried to merge them into a single interlinking universe – building towards an ensemble Avengers film. So a Thor film was inevitable; that it would be directed by Kenneth Branagh was not.

This has been described as a shocking comedown for Branagh – but actually getting the job was a remarkable achievement for a man who has mostly directed Shakespeare or very bad films.

Any other director who had a CV containing that, Dead Again and the Sleuth remake would be lucky to be handed a Go Compare ad. I guess, having played Wallander, they must have assumed he was an authority on all things Scandinavian.

Thor, though, is by no means a bad film, but it is harmed by a clumsy dual narrative that is half yet another superhero origins film and half sword and sorcery fantasy.

The scenes on earth where a group of scientists, led by Portman, are trying to work out who this strange unearthly beefcake (Chris Hemsworth), who has landed in the new Mexico desert, is are quite enjoyable with a nice line in humour.

But we keep getting returned to the struggles of King Odin (Anthony Hopkins) on his dull and humourless home planet Asgard, which the special effects budget can't really do justice to.

Hemsworth is a likeable screen presence but he doesn't project wild Viking warrior; more frontman in a Christian heavy metal band.

Marvel asserts a rigid and frugal control over its film output and has maintained a steady level of supreme but uninspiring competence.

Like all their films, Thor is all right, which will do for projects like Iron Man or hulk, but maybe not for Thor. As a kid, Thor didn't sit right with me and he still doesn't.

Unlike all the proper heroes, who quite plausibly got their powers through the capricious whims of benign radiation, he was a figure of ancient myth. They are incompatible traditions, like trying to mix Merlin and Robin Hood.

Thor (12A)

Director: Kenneth Branagh

With: Chris Hemsworth, Natalie Portman, Anthony Hopkins, Stellan Skarsgard, Kat Denning and Idris Elba

Length: 114 mins

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