A disturbing portrait of internet chatrooms is magnified for commercial pleasure in the new cyber-thriller Unfriended, a movie that could just as easily be renamed “I Know What You Did On Facebook.”

The film is at its core a slasher movie in digital disguise and that’s not a bad thing, at least for the first two-thirds. Taking place entirely online and in real time, we are quickly introduced to each of our main characters, young movie stereotypes who are seen checking their Facebook pages, updating iMessage or just randomly browsing the internet. But slowly the point of our voyeurism into these characters’ lives shows us that these kids share a recently deceased classmate. It turns out certain details of her death still remain a mystery, and when the core group each start getting creepy messages from the great beyond, movie logic tells them the first thing they should do is jump into a chatroom and figure out the details online.

Setting up your film from a laptop’s point of view is an interesting gimmick that director Levan Gabriadze uses to his advantage quite well. We see everything our characters see, from the furious typing on their keyboards to the innocuous indifference of checking their Facebook status. When things are taken up a notch and our heroes start disappearing themselves, that’s the point where Unfriended excels at using the multi-camera angle to full effect. The scares and the central mystery begin to take hold and the movie peaks with these very intense scenes, leaving most moviegoers checking over their shoulder once the movie is long over.

That’s the good news.

Sadly, Gabriadze and his crew decide to take things a step further into the supernatural for the film’s climax and that’s where Unfriended begins to lose steam. There’s always a delicate balancing act with filmmaking. As a storyteller, you want to captivate your audience, but not lose their interest by going a step too far. In the case of a horror thriller like this, you want to pace out your scares and carefully build tension without relying on unnecessary jump scares. Those are cheap ploys to manipulate your audience and the easiest way to signal your film is in trouble.

For the most part, Unfriended grounds its story well and creates a hypnotic cyber atmosphere that will be instantly recognizable to anyone who lives in a digital universe. Even when our suspension of disbelief is threatened and central characters begin to act like characters in a horror movie, we are still attached enough to care about their safety. But once that final nail drops and we’re introduced to what is really going on, that’s where this delicate house of cards falls apart.

Unfriended benefits most from its online setting, giving it a look that feels fresh and more than just another genre movie. The ending may be a letdown, but the film’s sharp sense of dread that precedes the unfortunate misstep is still worth a mild recommendation.

Rating: B-

Unfriended opens in theatres nationwide April 17.