‘Unfriended’ Horror flick plays on genre’s staples with a digital twist as teens plagued by cyber ghost

Shelley Hennig and Moses Storm star in “Unfriended.” The actors shot many of the movie’s live action scenes with GoPros.

A skinflint’s dream, “Unfriended” either raises or lowers the bar for low-budget, big-studio synergy. More provocative sizzle than bloody-disgusting steak, it features a small cast of whozat young actors and was directed by another question mark, Leo Gabriadze. The most recognizable name is Timur Bekmambetov, the cult filmmaker (“Night Watch”) turned Hollywood name (“Abraham Lincoln: Vampire Hunter”), who cooked up the idea of making a movie that unfolds almost entirely on computer windows. One of Bekmambetov’s former employees, Nelson Greaves, wrote the script, and they both helped produce.

The story is basically Agatha Christie’s “And Then There Were None” retooled for the social-media age. Six blank-slate teenage friends convene one evening on Skype for some idle yammering only to be interrupted by a troll or perhaps a poltergeist now virtual-squatting in their screened-in world. The intruder may be Laura Barns (Heather Sossaman), a friend of the six who killed herself after being bullied online. The intruder-troll-dead girl doesn’t have much of a sense of humor, and, after baiting the jittery Skypers, it gets down to progressively violent business. It cannily uses an arsenal of classic scare tactics (loud bangs, dim lights) but is never creepier than when deploying the kinds of cruel taunts, gleeful insults and ugly threats that are the Internet bully’s stock-in-trade.

The best thing about “Unfriended,” beyond its funny-nasty title, is that it doesn’t play as remotely dull as it sounds even if most of the drama takes place inside shifting, overlapping windows. In other words, most of what you’re watching looks a lot like your computer, especially if, like Blaire (Shelley Hennig), you’re a multitasking teen who likes chatting with besties on Skype while simultaneously instant messaging (and sexting) your BF, Mitch (a good Moses Storm); checking out YouTube (for videos like “Laura Barns Kill Urself”); listening to tunes; and scrolling through horror-show websites.

Much of the live-action material was shot by the actors using GoPro cameras. As in Skype exchanges, their faces tend to loom in their respective displays, which Gabriadze arranges and rearranges like a blackjack dealer dealing assorted hands. Gabriadze and his postproduction team also play around with the image because much of what you’re watching is animation. They pixelate, smear and split the visuals, and interrupt and punctuate the dialogue with ominous crackles and static. These manipulations torque the tension and at times forecast other, more substantive violence to come.