The latest and fifth instalment in the long-running Transformers franchise re-imagines the Arthurian legend with giant robots, opens with a medieval battle sequence and heads rapidly downhill from there. It's 2 hours and 27 minutes long with what feels like 2 hours 25 minutes of relentless action. There might have been a plot, but it gets entirely lost in the unremitting battles, hackneyed characters and puddle-shallow dialogue.

The movie doesn't even have the good grace to not take itself too seriously, as ultra-hero Optimus Prime switches between good guy, bad guy and good guy again. If you're a fan of the franchise and about eight years old it may tick some boxes. Otherwise it is a relentless stream of staggeringly spectacular visual and audio effects… so, not all bad then.

Picture: Whether you watch the HDR10 or Dolby Vision 4K encodes, or 1080p iteration, your peepers are in for a treat.

While all are seemingly based upon a 2K DI, there's plenty of detail here, no doubt a benefit of beyond-4K source photography. And ...The Last Knight really dazzles in other areas. Viewed in DV, colours are stunning, contrast expansive and the image depth goes back into the screen for miles. The range of tones and detailed lighting levels is staggering – this is highlighted by the emerging ship, sea-scape and vanilla sky in Chapter 17, where the scene switches to the cornucopia of greys inside the ship and back outside again just to drive the visual spectacle home.
Picture rating: 5/5

Audio: There's Atmos audio on both the 4K and Full HD discs and the result is as classy as home cinema gets. Largescale dynamic effects and crisply articulate dialogue are all spot on, while use of the overhead layer is remarkably subtle, engaging for the swelling score, atmospherics and effects that are genuinely meant to be above the action – check out 'Bee's voice as he towers over a prone TRF operative at the end of Chapter 3.

It's a supremely impressive and complex mix all round, and not as mindlessly over-the-top as you might think.
Audio rating: 4.5/5

Extras: The bonus Blu-ray platter is packed with extras. Merging Mythologies does a better job of explaining the plot than the movie and Climbing the Ranks shows how the film's military look quite so believable in action. (Spoiler alert: they're real soldiers). There are also location featurettes and VFX analysis. A highlight is a sequence on how they brought production to the UK, and a brief cut to a terrified Anthony Hopkins in the passenger seat of a McLaren hurtling through London. 'How are you going to do Arthur and Merlin without going to England?' asks the director rhetorically.

We honestly enjoyed the extras more than the movie.
Extras rating: 4.5/5

We say: Incredible visuals and Atmos sound turn this shallow sequel into a home cinema hero.

Transformers: The Last Knight, Paramount/Universal Pictures, Ultra HD Blu-ray & All-region BD, £40
HCC VERDICT: 3.5/5