This instalment does manage two surprisingly clever things, though. First of all, it establishes Ben Foster's (3:10 To Yuma) Zobrist as a technology billionaire and biologist so obsessed with the planet's overpopulation he has created a man-made plague to drastically reduce humanity's numbers. Then the film kills him off in its opening minutes. After that, everyone is in a race against time to find his biological weapon before it is triggered.
Secondly, the film also strips our puzzle solving symbologist of his chief weapon – his brain. Reeling from a serious head wound, Langdon is plagued by apocalyptic visions and suffering from mild retrograde amnesia. The usually obnoxious mansplainer of the first two films is unusually vulnerable and initially dependent on Felicity Jones' (The Theory Of Everything) resourceful Dr Sienna Brooks for help. She is a former child prodigy who enjoys the usual millennial pastimes of working for Doctors Without Borders, marathon running and obsessing over Dante. The last hobby enables her to occasionally pre-empt Langdon's problem solving as they head into Florence on a Dante driven scavenger hunt, though her CV suggests she should be able to figure out the whole thing more quickly without him.
Despite that new blood, it is soon business as usual as Langdon races around Italian Tourism Board approved locations, vandalising works of art associated with Dante, in search of clues. Assassins march implacably after him, somehow figuring out the same clues as he does without the benefit of degrees in symbology – whatever that is. And international agencies positively bulging with suspicious employees chasing after them. In this version of reality, the World Health Organisation boasts a paramilitary force that kick down doors and have private jets on standby, which seems unlikely. Still, with the fate of half the global population at stake, perhaps they are simply, and justifiably, keen.
Aside from stray traces of Hanks charm sneaking through Langdon's dourness, it all soon becomes stiflingly dull. But just as you start to suffer museum fatigue, Irrfan Khan (Jurassic World) shows up to lift things a little as the head of a laughably shady organisation known as The Consortium, merrily throwing spanners in everyone's plans and looking good doing it. Frankly he is the best reason to watch the film's second half, which sees Howard exchange the streamlined kineticism of a race against time thriller for a bewildering tumult of reversals, flashbacks and contradictory information. Meanwhile a romantic subplot involving Sidse Babett Knudsen (Borgen) gives rise to an entirely irrelevant backstory. Not only that, but there is also a pointless side trip to Venice that stops the film dead just when it ought to be gathering momentum.
Never wanting to rest on its breathless trip around the ancient historical landmarks, things begin to pick up again in time for an explosive Istanbul climax that effectively uses sites previously featured in From Russia With Love (1963) – an appropriate touchstone for a film whose hero acts more like a globe trotting James Bond than a fusty book scented academic.
In spite of all this, though, we are still left with a feeling of both missed opportunity and nagging frustration. Having already adapted two Dan Brown outings, shouldn't this have been the one where Ron Howard finally got it right?
The backdrop may be outrageously scenic, but the revelations in this tale are much too easy to spot coming, and after setting up an interesting ethical dilemma about humanity's future – the real risks from over population – it utterly ignores it for the usual bad guy posturing. For a film about smart people being smart, you just wish the plotting were a little more nuanced.
It may not be the worst of the trilogy, but Inferno is ultimately less for fans of thrillers and more for people who are planning a holiday in Florence.