In October 1994, college students Heather Donahue, Joshua Leonard and Michael Williams disappeared in the woods near Burkittsville, Maryland, while shooting a documentary about local legend the Blair Witch. When "The Blair Witch Project," directed by Daniel Myrick and Eduardo Sánchez, premiered at the 1999 Sundance Film Festival, it became an overnight sensation. Billed as a legitimate doc—and more specifically, the actual discovered footage of these three missing persons—the shoestring-budgeted film quickly grew in mystique as its novel cinéma-vérité approach and then-groundbreaking Internet-based promotion turned it into the must-see event of that summer. Of course, "The Blair Witch Project" wasn't really real, made by savvy filmmakers and talented actors standing at the frontier of a fresh, genre-begetting zeitgeist. Nevertheless, the picture's first-person POV storytelling continues to reverberate seventeen years later, even as few imitators have come close to matching it in terms of its stark, down-and-dirty authenticity and harrowing intensity.

Ignoring the events of Joe Berlinger's ambitiously different, largely misunderstood 2000 sequel, "Book of Shadows: Blair Witch 2," the simply titled "Blair Witch" reimagines an alternate continuation that is stylistically at one with the original movie. Under these found-footage parameters, director Adam Wingard and writer Simon Barrett (2013's "You're Next") have conjured what modern-day viewers will likely be expecting from a 2016 update. It's ramped up, more obvious in its fright tactics, and holds only about half of its predecessor's human complexity. Once it gets going, though, it works like gangbusters. Expanding upon the mythology of witchy 18th-century hermit Elly Kedward and long-dead child murderer Rustin Parr, "Blair Witch" unleashes its new characters into a desolate maze of trees and underbrush that grows to more closely resemble Hell. By the end, even the most hardened audience members are apt to get a case of the jitters.

When Heather went missing in 1994, her little brother James (James Allen McCune) was just four years of age. Two decades later, sparked by a new DV tape purported to have been found in the Black Hills Forest by local vloggers Lane (Wes Robinson) and Talia (Valorie Curry), James is reignited with the slim yet possible hope his sister is still alive. While the house seen at the end of Heather's tape has never been found, he is determined to find it. Stocked with memory cards, a camcorder, over-the-ear video cams and a drone, James, gal pal Lisa (Callie Hernandez), best friends Peter (Brandon Scott) and Ashley (Corbin Reid), and guides Lane and Talia head into the woods. When Ashley accidentally steps on a shard of glass while crossing a creek, everyone hopes her injury will be the worst thing to happen to them during their expedition. They are sorely mistaken. Unable to find their way back to their cars as time begins to play tricks on them, their overnight camping trip becomes a fight for survival. All the while, the group moves closer to the truth about Heather's fate—and the malevolent legend that haunts the area.

"Blair Witch" is a slicker production than "The Blair Witch Project" by the very nature that technology has improved in the intervening years, but it succeeds all the same as an expansive companion piece, very much in the spirit of that masterfully suggestive horror watermark. Director Adam Wingard falls back on jump scares far too much, the kind where a person suddenly leaps into frame just as everything has gone silent. It's an old-hat trick that can work in the right circumstance, but this film repeats it so many times that even an exasperated Lisa finally exclaims, "Would everyone stop doing that?!" Unfortunately, they don't stop doing that, and it is the one moldy convention in a supernatural terror show that genuinely unsettles once a series of freaky, unexplainable occurrences kick things into high gear. Wingard is a phenom when it comes to provoking a particular mood and building a wave of suffocating portent, and he achieves both of these things while also finding unexpected beauty in his lurid landscape.

The most lingeringly creepy moments rely on uncomfortable situations and the kind of ghastly, almost subliminal imagery nightmares are made of. Ashley's gradually infected wounds lead to a number of squirmy run-ins, while her decision to climb a tree and retrieve their drone is both unimaginably dangerous yet deriving specifically from her desperation. The further the narrative presses forward into inexplicable weirdness—waking up at 7 a.m., James and Lisa are baffled why it is still dark outside—the better it gets. And, while the protagonists do not have the chance to explore the psychology and coping mechanisms of their traumatic experience the way Heather, Josh and Mike did, they are all likable, distinct individuals whom the viewer does not want to see fall victim to the evil forces surrounding them. Performances are natural across the board, all the better to complete the spell of reality, but it is newcomer Callie Hernandez who impresses most of all, taking her horrified Lisa to the emotionally hyperventilatory brink.

When so many horror movies start strong only to peter out by the end, "Blair Witch" does the preferable opposite. The demonic wonderland of a third act outdoes itself, spinning hauntingly out of control as the ramshackle house James and Lisa have been searching for all along comes into view. Placed on a storm-strewn, lightning-crashing path toward a destiny they do not want to confront but must, they press forward and into a wicked, topsy-turvy lair defying all reason and belief. Simply put, it is a tremendously satisfying climax, and not even the contrivance that they would still be wearing their over-the-ear video cams and lugging around a camcorder can dampen the breathless fun. "Blair Witch" is no "The Blair Witch Project"—few films are—but it is a worthy, affectionate follow-up with nerve-blistering apprehension to spare.