“Night Swim,” the confident feature debut of director Bryce McGuire (sharing a story credit with Rod Blackhurst), is not a King creation. But it has all the earmarks and classical virtues of the horror master’s tightest riffs: believable middle-class Americans who throw backyard barbecues and play sports, grappling with the supernatural, their pop-culture distractions falling away in the presence of something unexplainable. Most redolent of King, the movie cultivates a strong undercurrent of economic status-jumping. As one character humble-brags, “We have a pool,” the camera zooming in on smiling eyes.

That’s Ray Waller (a lanky, perfectly cast Wyatt Russell), until recently a hard-hitting Brewers third baseman who’s just received a prognosis of multiple sclerosis and is already emitting sad loser stink. But his devoted wife, Eve (“The Banshees of Inisherin’s” Kerry Condon), sees an opportunity for rekindling, and, as they and their two kids settle into their new suburban home, spirits are on the mend. Ray’s doctor, unsparing in her honesty, recommends water therapy.

We’ve already seen what the Waller pool can do in a PG-13-yet-impressively-tense prologue set in 1992, night lights fluttering, the drain emitting a dark cloud of goo, a young girl gobbled up. This incoming family knows nothing of that, but already, their housecat, Cider, feels like a goner. Moreover, Ray seems to be getting better, doing ferocious laps after midnight and training for either a second chance on the playing field or a decent shot at becoming the Nicholsonian patriarch of his own version of “The Shining.”

Wyatt Russell in the movie “Night Swim.”

(Universal Pictures)

McGuire, who executed a trial run of this concept with a 2014 short film, knows exactly what he’s doing, scene after scene, especially when it comes to the deliciously sadistic grammar of suspense. He turns casual watermelon slicing into a squirm-in-your-seat ordeal, ditto a teenage round of Marco Polo (with one uninvited guest), and knows that we’re most vulnerable right after a big laugh. You’re even ready to forgive McGuire some of the script’s more boneheaded lines (“There’s something wrong with that pool…”) because the pacing and craft is so tight.

No points for comparing these deep-end underwater shots to “Jaws” or, more aptly, the Spielberg-produced house of horrors “Poltergeist,” neither of which can be improved upon. Yet the ambition here is invigorating and, during its most exhilarating stretches, “Night Swim” seems to be actually pulling it off — until suddenly it’s not, a victim of overplotting, pushing the water thing a little too hard. (There’s plenty of room in the pool, but enough for mystical spring ponds, an ancient curse and parental guilt?)

It won’t be the first horror movie unable to tie things up neatly. Even King struggles with that. But how lovely that January has become a month when a savvy studio like Blumhouse (last year‘s “M3gan” was also theirs) can sweep in and remind us that, once in a while, the old house ain’t broken and requires no fixing. Just maybe a pool cleaner.