A radically fresh, hair-raisingly inventive take on a thought-worn subgenre, "It Follows" is supernatural horror as imagined by a filmmaker—that is, writer-director David Robert Mitchell (2011's "The Myth of the American Sleepover")—who has no interest in rehashing the commonplace. Opting for mood-drenched foreboding over obvious jump scares, the film whittles its way into the viewer's increasingly skittish subconscious while proffering a stack of underlying metaphors and themes—about the loss of innocence, about the perils of sexually transmitted diseases, about the struggle to find purpose, acceptance and responsibility in a post-adolescent existence—that reveal it as so much more than just a pedestrian boo machine. In spite of its stop-and-start narrative structure, few motion pictures achieve the level of usurping dread that "It Follows" manages.

19-year-old community college student Jay (Maika Monroe) has only been out a few times with Hugh (Jake Weary), but they get along well and seem to be hitting it off. Shortly after sleeping with him for the first time, she muses about how, as a child, she couldn't wait to be older so she could go on dates. The sky seemed to be the limit back then, the entire endless world spread out before her. Now, however, reality has set in, and it is so much more horrifying than she could have ever imagined. Hugh has infected her with a potentially deadly disease, one that materializes itself in the form of an ever-changing specter that only she can see. It doesn't think, or feel, but it will follow her on foot, ceaselessly and with only one purpose: to take her life. The only way to pass the infection to someone else is through sexual activity, but if said person falls victim, it will return to the previous owner, a never-ending chain that quite possibly can never be stopped.

"It Follows" is attention-grabbing from scene one, as frightened teenage girl Annie (Bailey Spry) tears out of her house and spills onto her quiet suburban street. She acts like something is after her, but not a neighbor getting groceries out of her car, not her concerned father, and not even the viewer sees anyone else there. Annie finally drives away and escapes to the beach, but an apologetic phone call to her dad will be the last time he hears from her while she is alive. As the film segues to protagonist Jay, sister Kelly (Lili Sepe), and their friends Paul (Keir Gilchrist) and Yara (Olivia Luccardi), a sense of laid-back, unhurried normalcy gives way to looming portent when Jay heads to the movies with new beau Hugh and an unknown something spooks him out of the theatre. She tables her concerns for the time being, not learning of the full gravity of what was bothering him until it is too late for her to turn back.

The ingenuity of David Robert Mitchell's screenplay is in the creation of an ominous force that isn't quite like any other past cinematic figure of villainy. A complete and utter mystery, it cannot be reasoned with or properly understood, yet it keeps coming. This concept of an evil that is pulled like a magnet toward its tainted target, slowly but surely headed in his or her direction no matter the distance traveled, is the picture's most chilling aspect. As the physical embodiment of this malevolent presence keeps reinventing itself, so, too, does Disasterpeace's phantasmagoric music score, alternating through a blizzard of nerve-shredding aural motifs and synthesizer beats. Meanwhile, Jay and her friends' nondescript, seemingly uneventful Detroit neighborhood hides shadowy secrets every bit as dangerous as the dilapidated buildings and crime-ridden city streets they have been warned all their lives to avoid.

In a film that listens to its youthful main characters while treating many of the over-21 participants like adults in a "Peanuts" cartoon, Maika Monroe (who previously impressed in 2014's gravely overlooked "The Guest") is phenomenal as Jay. Attractive yet kind, touchingly idealistic until the rug is pulled out viciously from under her, Monroe has the charisma and fortitude to give Jay a fighter's spirit to go along with her outright fear and battered vulnerability. The actors around her are naturals and—with the exception of Keir Gilchrist (2010's "It's Kind of a Funny Story") as Jay's most steadfast protector, Paul—unrecognizable from previous credits on their résumés. They are wholly believable in their roles, with Lili Sepe standing out as Jay's high-school-aged sister, Kelly.

In "It Follows," an entity is closing in on Jay, yes, but so are the actualities of adulthood. Trapped not only by their circumstances, but by the sharp truth of mortality itself, she and her pals (who, in a refreshing change, quickly come around to believe her) set out to buy time as they plot their retaliation. Mitchell's direction is fueled by an unquenchable anxiety deceptive in its subdued pacing. Admittedly, there is at least one questionable blip in the rules he establishes and a few harrowing situations that weaken the story's momentum by cutting too soon. Because of this, the payoffs to the scares are inconsistent and do not quite reach their fullest capable heights. Fortunately, the singularly rich and mystifying atmosphere the director orchestrates never falters. The open-ended concluding scene is destined to divide audiences, but the jittery, unsure note it leaves one on is as it should be. Whether or not Jay figures out how to defeat her pursuer is beside the point. With her presumptions of security shattered forever, she now knows all too well that safety is but a tissue-thin illusion.