By Katie Walsh, Tribune News Service

Imagine a less spry and agile Indiana Jones and you have Professor Robert Langdon (Tom Hanks), a Harvard professor of religious iconography and symbology (not a real academic discipline). He’s riddled his way from the page to the screen in the wildly popular “The DaVinci Code,” and “Angels &Demons,” adapted from Dan Brown’s series of quasi-religious, art history-inspired mystery novels most likely to be found on the shelf of an Airbnb rental. Now imagine a less spry and agile Indiana Jones in “The Hangover,” with shades of “Contagion” wafting about, and you have the third film in the trilogy, “Inferno.”

In “Inferno,” Langdon wakes up in a Florence hospital bed with one heck of a hangover. He’s beset by horrible visions of wrecked bodies with backwards heads covered in skin pustules, men in beaked masks, a mysterious woman on a fiery street. He’s got a head wound, no idea where he is, and the worst migraine of all time. Director Ron Howard, who also helmed the previous two installments, takes the head trauma as an opportunity to experiment with an edgier form and style. The screeching noises, flashing lights, rapid editing and queasy camera movements will make you too feel like you’re experiencing head trauma.

Amnesiac Langdon is rapidly whisked out of the hospital by an attentive doctor, Sienna Brooks (Felicity Jones), who happens to be a fan of his work. He’s got a “Faraday pointer” secreted in his clothing (essentially a laser that projects an image of Dante’s Inferno). They decipher the coded image and link it to an eccentric billionaire bioengineer, Betrand Zobrist (Ben Foster), who has conveniently laid out in a YouTube lecture his radical theories about global overpopulation and thinning the herd with a weaponized virus, for the good of the planet.

So off run Robert and Sienna, jogging around Italy, pursued by SWAT teams of the World Health Organization, as they go on a scavenger hunt from precious antiquity to precious antiquity, looking for clues as to how Robert got this Faraday doo-hickey and where Zobrist’s deadly, apocalyptic virus might be deployed that night at midnight.

The twists in the story keep on coming, at the expense of the plot’s structural integrity. There are a few moments where you’ll want to puzzle something out, but the story is relentless and doesn’t pause for a minute — suddenly Tom Hanks is wrestling a Turkish thug in a pool of water in the sunken baths in Istanbul, so there’s not one second to consider the plot holes.

The best thing going for “Inferno” is Hanks, who plays his befuddled professor Langdon with the right modicum of bafflement and brilliance. He can’t believe he’s in this situation but also can’t turn his brain off. Jones makes a fine counterpart as a prim English child prodigy, an heir to his throne if only she can find the right motivation.

The cast is stocked with international talent including French actor Omar Sy as a questionable WHO agent and Danish actress Sidse Babett Knudsen as Langdon’s old friend and possible love interest. But it’s Bollywood star Irrfan Kahn who slyly steals the show as a private security operative. He brings possibly the only humor in the film playing an exasperated corporate type fed up with his client. It’s a levity that’s much-needed in the cacophonous chaos of “Inferno.”

‘Inferno’ (2 stars)

Tom Hanks returns as renowned Harvard professor Robert Langdon, trying to thwart a billionaire bad guy’s plan to unleash an apocalyptic virus on humanity. The invariably-reliable Hanks helps make the plot’s gaping holes and “DaVinci Code” silliness go down easy. With Felicity Jones as the intrepid professor’s acolyte.

Rated: PG-13 for sequences of action and violence, disturbing images, some language, thematic elements and brief sensuality.

Showing: Alderwood Mall, Cinebarre, Everett Stadium, Galaxy Monroe, Marysville, Stanwood Cinemas, Meridian, Sundance Cinemas, Thornton Place, Woodinville, Cascade Mall, Oak Harbor Plaza