Getting what you wished for often doesn’t turn out well in real life. But it never turns out well in horror films, as the new movie from Curry Barker vividly demonstrates. Trafficking a well-worn theme — the classic short story “The Monkey’s Paw,” the exemplar of the concept, dates all the way back to 1902 — Obsession makes it fresh and original with its superbly orchestrated blending of dread, jump scares and dark comedy. The film represents an instant breakout for its director-screenwriter, who first received attention with his YouTube comedy sketches created in collaboration with Cooper Tomlinson (one of this film’s supporting players) and his extremely low-budget horror film Milk & Serial. It’s another example of how the horror genre has become a launching pad for ambitious filmmakers.

The central characters are Bear (Michael Johnston, MTV’s Teen Wolf), a dweebish employee at a musical instruments score, and his co-worker Nikki (Inde Navarrette, Trap House), on whom he has a helpless crush. And by helpless, we’re talking desperate, and thoroughly relatable to the vast majority of the population. Watching his romantic anguish with concern are the pair’s mutual friends Ian (Tomlinson) and Sarah (Megan Lawless), the latter of whom secretly pines for Bear herself.

Bear is hopelessly trapped in the friend zone, so when he’s looking to buy Nikki a gift after she accidentally loses a necklace and he comes upon a unique item in a novelty store, he’s immediately intrigued. It’s a “One Wish Willow” (the film begins with an amusing fake commercial for the product), which promises its users that it will grant one wish upon splitting it in half. And for a mere $6.99, it’s a steal. Except rather than giving it to her, Bear impulsively uses it himself.

It’s no spoiler to reveal that the product works as advertised, with Nikki undergoing an immediate personality transformation as soon as Bear wishes that she would love him more than anyone in the world. For a while, he relishes her passionate affection and sexual voraciousness. But it soon becomes apparent that, like so many new relationships, this one has a dark side. A very dark side, with Nikki exhibiting the sort of extreme possessiveness that would put Fatal Attraction’s Alex to shame. (Speaking of which, Obsession is likely to do for cats what that film did for pet rabbits.)

What makes Obsession so fun, and so disturbing, is how it takes typical aspects of dysfunctional romantic relationships to initially comic and then horrific extremes. The film provides further complexity by not making Bear a sympathetic victim but rather complicit by initially enjoying Nikki’s affections despite their artificial provenance. Until, of course, they get out of hand. Johnston displays an admirable willingness to make his character look pathetic at times rather than trying too hard to make him likeable.

It’s Navarrette, though, who truly gives the film it’s mojo. The young actress delivers such a virtuosic performance as the spellbound Nikki that she’ll induce nightmares for anyone who’s ever wondered what exactly the hell is going on with their romantic partner. She’s truly frightening in her intensity, and also induces pity whenever her character briefly toggles back to her unpossessed state in helpless confusion. It’s a breakthrough turn that should guarantee plenty of work for her in the years ahead.

Obsession has more than its share of shocking moments, with one sudden, brutally violent attack coming so out of nowhere that you’re left reeling. But Barker also has the confidence to draw out the suspense slowly (sometimes too slowly, as the film could stand to lose a bit of its 110-minute running time) and let the tension accumulate. It was recently announced that the filmmaker will be directing the upcoming reboot of The Texas Chainsaw Massacre. What seemed like something to dread now actually inspires hope.