In his final “Daily Show” broadcast, Jon Stewart offered some sage advice to viewers about what he’d been sniffing out for so many years: “If you smell something, say something.” If people follow that admonition, viewers unlucky enough to see “The Man from U.N.C.L.E.” may be shouting warnings from the rooftops. Guy Ritchie’s elaborate but flat-footed reboot of the 1960s TV series—which was about a pair of agents, one American and one Russian, who, under the auspices of the secret international organization (the titular acronym), fought a sinister outfit called THRUSH—is a misfire on virtually every level. In script, casting and even cinematic technique—which has always been the director’s strong suit—it’s close to being a total disaster. That distinguishes it from Ritchie’s two “Sherlock Holmes” movies, which might have been crude bastardizations of the classic character gussied up with all the vulgar trappings of modern action movies but at least boasted charismatic stars and technical know-how.

Certainly charisma is something of which neither Henry Cavill, the new Napoleon Solo, nor Armie Hammer, the Illya Kuryakin, could ever be accused; they’re two stiffs who can barely make it past the mannequin stage of acting. Cavill certainly tries to appear debonair as the supposedly suave Solo, here remade as an ex-master criminal compelled to join the CIA to avoid prison for his many crimes. But he comes across like a poor James Bond substitute, more George Lazenby or Roger Moore than Sean Connery or Daniel Craig. To be sure, Robert Vaughn was no great shakes in the TV series either, but that was fifty years ago and viewers were much more tolerant then; Cavill’s sophomoric effort to mimic him comes across as clumsily arch.

As for Hammer, he’s the same blandly handsome nonentity he was in “The Lone Ranger,” except that in this case he boasts a garbled Russian accent and has to do without the zanily over-the-top antics of Johnny Depp, who might have been giving a thoroughly corrupt performance as Tonto but helped his co-star by so overshadowing him that his inadequacies weren’t so noticeable. The smugly smooth Cavill doesn’t provide a similar degree of camouflage.

There’s a third star in the picture, though she doesn’t get as much screen time as her male companions. It’s Alicia Vikander, who made such a great impression in “Ex Machina.” She plays Gaby Teller, an East German mechanic who, as the film opens against the background of Civil War tension in 1963, becomes the key to foiling a dastardly plot by a group of fascists to acquire—and use—an atomic bomb. She’s the daughter of a German rocket scientist, described as Hitler’s favorite, who’s been missing since the war’s end and is reported to be the key to the bomb scheme. In a big opening chase sequence, Solo and Kuryakin vie over the girl, the former trying to get her across the Berlin Wall to the western sector and the latter trying to prevent it.

That’s the best action scene in the picture, mostly because it involves two junky-looking communist-era cars souped-up to become hell on wheels—one of the movie’s few decent sight gags. Soon afterward, though, the two spies’ rivalry turns into partnership when the CIA chief (Jared Harris) and his Russian counterpart inform them that they must work together to defeat their countries common fascist enemies. Kuryakin will impersonate a Russian architect who’s Gaby’s fiancé, accompanying her to Rome to meet her Uncle Rudi (Sylvester Groth). Rudi, an unregenerate Nazi and as it turns out, expert torturer, is working for Victoria and Alexander Vinciguerra (Elizabeth Debicki and Luca Calvani), shipping magnates who are the masterminds of the nuclear scheme. Cavill will revert to his former life to play a master thief who will worm his way into Victoria’s bedroom. Working together, the trio are to infiltrate the fascists’ lair, find Professor Keller, defuse the bomb and take charge of an oversized computer disc that contains all the details of the rocket assembly. (“Whoever has it, will control the world,” we’re told with no further explanation.)

Naturally things do not go as planned. Myriad break-ins and chases, a torture sequence, and a major betrayal—or at least what seems like one—intervene before all is put right, and yet another figure enters the picture—a Brit named Waverly (once Leo G. Carroll, now Hugh Grant), whom some will remember from the TV series. A major problem is that none of the action sequences are particularly well staged. An initial fight between Solo and Kuryakin is a shambles, and a protracted chase over lakes and mountain roads, comes across as a mess. A third—the siege of the villains’ island lair—is shown in what amount to cartoon panels on multiple split screens, presumably to recall sixties efforts like “Modesty Blaise,” but the effect is simply dull. And when an attempt is made to inject humor into them, the effort falls flat. That’s especially true in two sequences in which the action occurs in the background while the camera is focused on what’s happening in front of the mayhem (the first featuring a boat chase, the second a villain in an electric chair). Both are potentially funny moments spoiled by the ham-fisted way in which they’ve been directed and edited by Ritchie and James Herbert.

On the other hand, there’s some visual pleasure in watching Vikander in an array of swinging sixties glamour costumes even if she’s not given enough to do in them, and Grant is still capable of bringing some raffish charm to his few scenes, although the material itself is poor. And though Debicki and Calvani are nondescript villains, Groth has a good old time playing the sneering but cowardly Rudi. Oliver Scholl’s production design, the art direction team headed by James Hambridge , Francesco Alberico’s set decoration and Joanna Johnston’s costumes work together to ape the garish look of sixties “international” flicks, and John Mathieson’s widescreen cinematography is, with a few overly dark exceptions, thoroughly professional.

With very few exceptions, movies based on old television shows haven’t worked out very well. In terms of the spy genre, this one is more like “The Wild Wild West” than “Mission: Impossible.”