With the exception of John Woo's undercooked second instalment, Mission: Impossible has been that rarest of things: a major action-movie franchise which improves (or at least avoids diminishing) with each new iteration.

2015's Rogue Nation was arguably the best of the lot, with Sean Harris excellentl as the implacably villainous Solomon Lane, and Rebecca Ferguson the most engaging foil the series has yet found for the tireless Tom Cruise. With these two returning alongside the ever-present Cruise, Fallout could and should have been a slam dunk.

Instead, it's a damp squib, bogged down by a plot that manages to be convoluted and predictable at the same time, alongside turgid dialogue and stilted performances.

On the upside, Fallout's stunts are as adrenaline-pumping as any previous M:I film, with eye-popping visuals throughout, all shot and performed superbly. These sequences noticeably lack the innovative staging and high-wire tension which characterised their predecessors, though: the classic suspension-rig routine from the first film, or the projection-based subterfuge inside the Kremlin from Ghost Protocol.

Instead, we get a succession of blunt-force traumas: big, muscular punch-ups, car chases and explosions. This kind of uncomplicated energy is fine for your average big summer blockbuster, but the absence of the inventiveness which characterised previous M:I films is a disappointment.

When the action-sequence dust settles, this lack of ambition becomes more of a problem. Harris and Ferguson, along with the otherwise-excellent Angela Bassett, are given relatively meagre screen time, dominated by tedious exposition, unintentionally hilarious attempts at pathos and smirking pantomime villainy respectively.

They're shunted aside to make room for Simon Pegg and Ving Rhames to go through the motions once more, Vanessa Kirby as Cruise's latest age-inappropriate object of sexual tension. and Henry Cavill doing his usual turn as a very angry man with big muscles who is incapable of expressing any emotion.

All of them are pulled along by a plot whose strings are always visible, suspended haphazardly between those big action sequences: where previous films felt taut and incisive, and generally managed to fit some interesting character development between the tentpole moments. This time, we get some poorly-written one-liners, a couple of hopelessly signposted plot twists, and a bit of half-baked musings on Ethan Hunt's morals.

The overall effect is deadening, and lowers the stakes to barely-perceptible levels. We don't understand or care about these characters, despite the elaborate peril they're placed in. An hour or so in, it starts to feel like the spectacular stunts have been left to compensate for the dramatic hole at the film's core; by the end, it's clear they've failed.