The genre mishmash — “mashup” would be an overstatement — that cranks up "The Watch" might sound fresh: guy-centric goofiness meets sci-fi, with a dash of marital coming-of-age story. But the feature feels like part three of a past-its-prime franchise. That might be because topliners Ben Stiller and Vince Vaughn are playing the guys they always play, or because the script, credited to Jared Stern, Seth Rogen and Evan Goldberg, moves lazily from setup to punchline to setup, with no particular point and almost no punch. 

It’s not likely that a big-screen alien invasion has ever felt less urgent. But as the highest-profile comedy to hit theaters since last month’s "Ted," the Fox release is sure to pull in strong, if not stratospheric, numbers. 

Originally called "Neighborhood Watch" and changed to the more generic title after the fatal shooting of Trayvon Martin, director Akiva Schaffer’s pic is set in the fictional Glenview, Ohio, played by Atlanta as a generic suburban fantasyland lined with oversize houses. Stiller’s Evan Troutwig manages the local Costco, which turns out to be HQ for the invaders — the idea of big-box one-stop shopping for planetary takeover one of the movie’s better jokes among the predictable shock-value guy talk.

Video from THR: 'The Watch' outtakes trailer: Stiller, Hill, Vaughn and Ayoade goof off

A civically inclined yet angry milquetoast, Evan spearheads a neighborhood watch after the brutal, mysterious murder of one of his employees, a night guard (Joseph A. Nuñez) who happens to be a newly minted American citizen but is, more crucially, Expendable Victim No. 1. The recruits are married party guy Bob (Vaughn), wannabe cop Franklin (Jonah Hill) and newly divorced Brit Jamarcus (Richard Ayoade). 

The latter two lend the proceedings a bit of unpredictable character, although the maladjusted Franklin’s bedroom arsenal might give some viewers pause in light of recent horrific events. Vaughn adds a layer of paternal hysteria to his patented loudmouth, as Bob tries to rein in teen daughter Chelsea (Erin Moriarty) and quash her hotshot boyfriend (Nicholas Braun). 

Schaffer, a vet "SNL" writer, tries to frame the quartet’s heroic misadventures with complicating friction: They’re continually tormented by a snarky cop (Will Forte), and Evan is trying to evade facts with his eager-to-procreate wife (the talented Rosemarie DeWitt, doing what she can with a paper-thin role). But mainly the film proceeds by gags, with at least as many misses as hits. The guys discover an alien weapon that shoots lethal lasers (cue montage of them blowing things up); the guys capture one of the skeletal aliens (cue montage of them posing for “funny” photos with said alien). The monster itself, a combination of live-action and digital effects, has the look of an oversize insect and oozes the requisite slime. 

Video from THR: Fox changes 'Neighborhood Watch' to 'The Watch' after Florida shooting

Its m.o. of skinning victims and donning human exteriors introduces a "Body Snatchers" element and the kernel of a good movie. Knowing that invaders are passing themselves off as members of the Middle American community naturally gives rise to paranoia — a good fit for the mistrust and disaffection that Stiller can be so good at conveying. But though he gets to run with mechanical fury like an "MI"-franchise Tom Cruise, the edgier aspects of Evan’s personality are downplayed, even in his run-ins with a creepily attentive new neighbor. An uncredited Billy Crudup plays up the neighbor’s weirdness, while Andy Samberg cameos in the disappointing payoff to this strand of the story. 

With its polished but undistinguished design and visuals, "The Watch" wastes much of its running time on the expected bawdy shtick and man-cave musings. Tying it all up in unmemorable fashion are the usual lessons in being a grownup.

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