If you’re one of those people who take your Marvel superheroes a bit too seriously, you might not like Thor: Ragnarok.

You see, director Taika (What We Do in the Shadows) Waititi takes a 100 per cent irreverent approach to the source material, gleefully lampooning every character and comic book trope from the first frames to the last. If you’re sniffy about ‘maintaining a certain tone’ across the Marvel Cinematic Universe, or staying true to how certain characters are portrayed in the original comic books, you might find Thor: Ragnarok’s endless stream of laugh-out-loud gags borderline blasphemous.

For most people, though, the very stuff some fans might not like makes Thor: Ragnarok the most flat-out entertaining Marvel film yet. It gets close to even outdoing Guardians Of The Galaxy Vol. 2 for visual imagination and ‘broad’ humour  – and that it does this within the relatively serious world of Thor, Loki, Odin and new villain Hela (portrayed with gleeful charisma by Cate Blanchett) just makes the gags all the funnier.

Picture: While Thor: Ragnarok's 4K transfer delivers a worthwhile improvement on the 1080p Blu-ray that ships alongside it, it’s certainly not a best-in-class effort.

For starters, detail levels are only slightly improved over the HD picture. There’s a better sense of texture in clothing and hair during close-ups, and a slightly more defined sense of interior space. Some largescale shots, though – especially those of Asgard – actually look a little soft. And hardly ever do you get that snap associated with the crispest, cleanest transfers.

This may well be down to the 4K presentation being derived from a mere 2K digital master. But we’ve seen other 2K upscales perform better.

It falls to the 4K disc’s addition of HDR and wide colour gamut information to save the day. The brightness floor of pretty much the entire film is aggressively raised, making exteriors feel more natural and lifelike, and enhancing the punch and spectacle of the consistently colourful environments.

The colour palette doesn’t always seem to be pushed quite as high as the brightness, leading to the occasional washed-out hue. But it’s certainly strong enough to join with the HDR in delivering just the sort of flamboyant spectacle Waititi was surely aiming for.
Picture rating: 4/5

Audio: Having had our ears assaulted – in a good way – by Thor: Ragnarok at the cinema, the Dolby Atmos soundtrack included on Disney's UHD Blu-ray is a real disappointment.

At times the whole soundstage feels strangely compressed. You'll first notice this during the opening fight between Thor, Surtur and his minions/pet dragon. Accompanied – hilariously – by Led Zeppelin’s Immigrant Song, you’d expect this blend of rock and butt-kicking to shake your foundations and push every speaker into overdrive. But it doesn’t. Instead bass levels seem constrained, while treble details lack sparkle and punch. Even the mid-range sounds like it’s being held back, as if in preparation for some sudden barnstorming expansion that never comes.

There’s also surprisingly little use of subtle effects around the soundstage, and tellingly you have to turn your amp much louder than normal to get even a satisfactory sense of heft from the film’s many action scenes.

Whatever the reason behind this curious, er, mix up (the DTS-HD MA 7.1 soundtrack on the 1080p platter suffers from similar issues), Thor: Ragnarok sadly joins Avengers: Age of Ultron as yet another Marvel movie suffering from problematic home audio. You'd think by this point that Disney would have got its production processes running smoothly.
Audio rating: 3/5

Extras: The 1080p Blu-ray accompanying the 4K disc provides plenty of fun extra features to spin once the movie has finished.

The undoubted highlight is a hilarious chat-track by Waititi in which he’s far more likely to discuss the state of Surtur’s teeth or reflect on how little he remembers the shoot than bother with the usual ‘this is how we made this bit’ stuff. Hollywood studios should seriously consider getting him in to do an alternative commentary on every film…

The same jokey approach is enjoyably on show with the handful of behind-the-scenes featurettes provided here, making them more watchable than most. Five deleted/extended scenes are enhanced by more of the same humour too, while being able to watch two of the film’s biggest set pieces rendered as 8-bit video games is an unexpected treat. Yet more enjoyable madness comes courtesy of a Team Daryll spoof documentary in which Jeff Goldblum's Grandmaster shares a flat with a (very) Average Joe on Earth.

The only disappointments are a shallow recap of 10 years of the Marvel Cinematic Universe, and a gag reel that runs to just a couple of minutes.
Extras rating: 3.5/5

We say: Marvel's latest is a riot of 4K HDR fun that's let down by an underpowered soundmix.

Thor: Ragnarok, Walt Disney, Ultra HD Blu-ray & All-region BD, £30
HCC VERDICT: 3.5/5