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“Non-Stop” is a sky-high downer. 
  
 What a waste of a great premise: a locked-room mystery at 30,000 feet. Liam Neeson plays an air marshal on a New York-to-London flight. Somewhere among the 150 passengers and crew is an extortionist threatening to kill innocent travelers one by one unless a large ransom is paid. How can the lawman thwart the plot? How can he even investigate without throwing the cabin into mass panic? 
  
 The gloomy prologue had me leaning forward in full upright position. The opening scenes, with Neeson pounding down a pre-flight cocktail of Scotch and breath spray, tersely peg him as a seriously flawed hero. Director Jaume Collet-Serra shoots the introduction in shallow depth of field, echoing Neeson’s woozy perspective. 
  
 We observe fateful details. Who is the fellow who knowingly offers Neeson eyedrops in the airport lavatory? Why does Neeson’s seatmate on the flight, Julianne Moore, have a surgical scar on her sternum? Rising star Lupita Nyong’o (“12 Years a Slave”) plays a seemingly minor role as an air hostess. Is that just a quirk of casting, or is she a key character in camouflage? The suspense fan in me was more than ready for takeoff. 
  
 Then the film tailspins from whodunit to whydidtheybother? Bodies start dropping. Taunting text messages appear on Neeson’s cellphone. Implausibilities pile up like luggage on a baggage claim carousel. The extortionist has an almost telepathic knowledge of Neeson’s background and minute-to-minute actions, and is a deadly sniper with a peashooter. Characters change their stripes from belligerent to heroic at the screenwriters’ whim. A near-mutiny among terrified fliers is quashed with a promise of free air travel. 
  
 Nothing stacks up, as the movie wallows in “Snakes on a Plane” absurdity. Logic is the first casualty in contrived thrillers, and this script, by an undistinguished committee of writers, murders it with a thousand wounds. 
  
 Physics takes a pounding, too. Once again we see a gunshot through the fuselage creating a catastrophic vacuum vortex that rips the plane’s hull apart. That’s impossible. The air pressurization system would compensate for a bullet-hole leak. It wouldn’t even ruffle your hair. And don’t even get me started about the absurd power-dive episode of zero gravity. 
  
 What a shame it is that Neeson’s best role in years is as a teensy plastic policeman in “The Lego Movie.” He’s a powerful presence, both in his athletic assurance (no creaky joints for this 61-year-old) and his mournful gravitas. Yet he’s becoming a synonym for mindless action-movie mediocrity. 
  
 From the A list to “The A-Team.” Now that’s a rough landing. 
  
 Colin Covert • 612-673-7186 ||||| About 10 minutes into “Non-Stop,” you realize the movie’s scratching a particular and pleasurable itch. A cross between a drawing room mystery and an airplane-of-fools drama, the film introduces a broad range of character types played by a rogue’s gallery of talent: Look, there’s Julianne Moore as the stressed-out businesswoman desperate for a window seat! There’s Corey Stoll, the late congressman of Netflix’s “House of Cards,” as a macho jerk! Ubiquitous character sleaze Scoot McNairy (“Argo,” “Promised Land”) as the twitchy guy in 22C! Michelle Dockery — Lady Mary Crawley of “Downton Abbey” — as Nancy the air hostess! And you can guarantee this is the last time Lupita Nyong’o, whose Oscar for “12 Years a Slave” is nearly assured, will have to play a supporting role as a stewardess. 
  
 Towering over them all is Liam Neeson, who, as usual, looks like hell. Is there an actor who has ever seemed more miserable about kicking butt? He plays Bill Marks, a US Marshal with past family tragedies and a present drinking problem who starts receiving threatening text messages while working a New York-to-London night flight. The faceless culprit wants $150 million wired into an offshore account or he’ll kill a passenger every 20 minutes. For added fun, he’s framing Bill as the perpetrator, a disgruntled public servant gone postal from grief and booze. 
  
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 Obviously, Neeson functions well in situations like this. Since “Taken” turned the Irish actor into an unexpected action star in 2008, he has become the thinking man’s Chuck Norris, cracking bones and dispensing vengeance with troubled Shakespearean gloom. “Non-Stop” is directed ably and anonymously by Jaume Collet-Serra, who guided Neeson through the nutty reverse-amnesia plot of 2011’s “Unknown,” and it’s basically a black-box set-up, a story line locked into its single airborne location. Because the villain could be anyone on that plane, the hero is able trust no one. Which only screws on Neeson’s tragic mask tighter. 
  
 Once we get past the opening scenes on the ground — character introduction by way of TSA, how you behave at the security checkpoint decreeing your philosophy of life — “Non-Stop” juggles suspense with occasional bursts of mid-air mayhem. Marks has to find the maniac, hide a body or two, flirt dourly with Moore’s Jen Summers, calm a little girl (Quinn McColgan) — if this were the ’70s, she’d be played by Linda Blair — consult with the Muslim physician (Omar Metwally) in 13D, and put down a violent insurrection by a splinter group of passengers led by Stoll. 
  
 There’s enough going on, and in tight enough quarters, that you’re willing to overlook the head-banging absurdity of the plotting, not to mention all those text-messages whirling like malevolent thought bubbles around the hero’s head. (This is now an accepted part of going to the movies: audiences staring at a screen watching characters stare at a screen.) Writers John W. Richardson, Chris Roach, and Ryan Engle bet that the central hook — Who’s the bad guy? How’s he doing this? — will keep us paying attention. And they’re right. 
  
 At a certain point, though, they have to address the question of why the bad guy, and that’s where “Non-Stop” falls apart. The movie has been developing the sillies for a while anyway, ever since Marks confesses his personal flaws and lousy parenting skills in an inspirational speech to the assembled passengers. There’s a zero-G dive in which a handgun floats right into the hero’s hand, but we expect dumb miracles in B-movies. 
  
 No, it’s the revelation of the villain’s motives that leaves you scratching your head and searching for the rewind. In fact, the film’s final 10 minutes are ridiculous enough to almost neutralize the enjoyable stupidity of everything that has gone before. “Non-Stop” comes in for a landing with a bang and a shrug, and Moore in particular looks like her luggage has been grievously mishandled. But she’s used to traveling first class. By now, Neeson knows what it means to fly coach. Maybe that’s why he looks so depressed. |||||


assistant: – Liam Neeson's improbable late-career resurgence as an action star continues this weekend with Non-Stop, a thriller in which Neeson plays an air marshal attempting to find a killer mid-flight. Critics are lukewarm on it; many enjoyed Neeson's performance, but many also complained about the plot, and the ending in particular. Here's what people are saying: Non-Stop's premise—"a locked-room mystery at 30,000 feet"—is great, but eventually it "tailspins from whodunit to whydidtheybother?" writes Colin Covert at the Minneapolis Star Tribune. "Implausibilities pile up like luggage on a baggage claim carousel. … Logic is the first casualty in contrived thrillers, and this script, by an undistinguished committee of writers, murders it with a thousand wounds." "Havoc is wreaked, guns are fired, fights break out, turbulence erupts, heads are banged," writes a bored Moira Macdonald at the Seattle Times. "You wish Samuel L. Jackson and some snakes might show up." Instead, you just get a "generic action thriller" that "goes exactly where you think it’s going." Manohla Dargis at the New York Times was fascinated by Neeson's character; "he's an excitable, volcanic wreck, which makes the state of his mental health into something of a parallel, secondary mystery." Neeson brings to the screen a "beauty etched by time and a still-imposing body" that moves with "grandeur." Yeah, the movie makes no sense, "but that's expected, uninteresting, and incidental." Ty Burr at the Boston Globe was also riveted as he tried to figure out who among the stellar cast was the bad guy. "At a certain point, though, they have to address the question of why the bad guy, and that’s where Non-Stop falls apart." The villain's motives will leave you "scratching your head" and the last 10 minutes are "ridiculous enough to almost neutralize the enjoyable stupidity of everything that has gone before."