At a time when horror movies from around the world desperately strive to say something Relevant about rapacious capitalism or banlieue violence or Abu Ghraib or whatever, Bertino’s impressive debut, The Strangers, evinces an old-school single-mindedness that’s quite refreshing: This movie’s sole purpose and function is to scare the living shit out of you. What’s more, Bertino, like John Carpenter before him, understands that while the occasional sudden shock can be effective, nothing on Earth is as creepy as a silent, motionless, impassive threat.

He’s got economy down, too. Even before the brief but unnecessary explanatory flashback, it’s abundantly clear that James (Speedman) has just proposed marriage to his girlfriend, Kristen (Tyler), and that she has very reluctantly declined. Once the unhappy couple arrives at the isolated country house that James has previously strewn with rose petals, however, they barely have time to dry their tears and begin renegotiating their relationship status before they’re besieged by a trio of motiveless killers decked out in nightmare masks. These spooky ciphers wield axes and knives, but it’s mostly the implacable, almost voyeuristic way that they stalk their prey that’ll have you denting the theater’s armrests. Imagine how Halloween might play if Michael Myers had a wife and teenage daughter as accomplices.

For a first-time filmmaker, Bertino demonstrates an intuitive grasp of composition and its potentially destructive effect on the viewer’s central nervous system. After about 20 minutes of unresolved tension, you’re already so conditioned that it’s nearly impossible to pay any attention whatsoever to the ostensible focus of a given shot. (As a bonus, this means you spend less time watching Speedman perform the overemphatic emotional cues that he mistakes for acting—it’s almost physically painful watching him go get the mail “as an angry, wounded guy would do it.”) Instead, your eyes dart nervously to and fro without respite, seeking out barely perceptible background motion and malevolent shapes in dark corners. Bertino, who also wrote the script, has no endgame in mind—the finale, while disquietingly bleak, feels like a failure of imagination—but it almost doesn’t matter. You’ll be too grateful when the bogeymen finally pounce.