A curveball from the diverse but typically more dialed-in Neil Jordan (The Crying Game; Breakfast on Pluto), the would-be thriller Greta is surprisingly campy, and yet not campy enough to work.

Following a long, slow buildup in which young New Yorker Frances (Chloë Grace Moretz) befriends the titular lonely widow (Isabelle Huppert) after returning the handbag the latter left on the subway, Frances rejects her mother substitute upon the overly-dramatic discovery that she’s not the first Girl Scout to be lured to Greta’s lair.

Taking a page from the Fatal Attraction playbook, Greta won’t be denied, yet despite the inherent mysterious menace in Huppert’s poker face, Jordan makes it a stretch in these circumstances to find the diminutive actress threatening.

Relentless text messages and voicemails are only so disturbing — they mainly beg the question of why Frances is unaware of her phone’s “block number” feature — but things get especially silly starting with a sudden cut to Greta stalking her prey at work, accompanied by a cliché musical sting that plays better as comedy than horror.

Atop such bonkers details like the swanky apartment Frances shares with Erica (Maika Monroe, It Follows), complete with a landline, one can’t help but laugh as Greta grows more desperate in her advances, throwing a bizarre public tantrum and dancing around her apartment like a ballerina to dispatch an intruder.

Though the film lays forth seemingly rich potential for more taut suspense, Jordan rarely presents the action in a tense manner, and his interest in visual ingenuity is even more sparse. Greta’s improbably active pursuit of Erica at a bar, complete with a string of photos sent to Frances, breaks that pattern, and the recasting of Franz Liszt’s lovely "Liebesträume" as nightmarish is likewise laudable.

In these moments and a few others, Greta hits its genre notes with striking and encouraging professionalism, yet far too often these soul-stirring instances are undermined by juvenile behavior and a sense of carelessness from behind the camera.

Grade: C. Rated R. Now playing at Biltmore Grande and Carolina Cinemark

(Photo: Focus Features)