Mercedes Bryce Morgan’s third film is a fascinating mash of genres that keeps its audience guessing. On the face of it, the 2024 picture is a punchy entry in the brewing Airbnb horror subgenre popularised by films like 2020’s The Rental and 2022’s Barbarian. Horror fans, however, may be surprised at how well they take to an opening hour of mystery that unravels as an awkward romantic drama before things take a dramatic turn for the bloody.

Struggling to work through some pending lifestyle changes, a couple, Sage (Maddie Hasson) and Diego (Marco Pigossi), take a weekend break at a large lakeside country house. The fractures in their relationship threaten to split open wide when they find the property double-booked with charismatic couple Will (Alex Roe) and Cin (Andra Nechita). The four agree to share the weekend, but things start to unravel when they unlock two mysterious doors in the house: one leads to a sex swing, and the other to an Ouija board surrounded by newspaper clippings of disappearances around Bone Lake.

Will and Cin pry more and more into Sage and Diego’s relationship, ruining Diego’s chance to propose and building on Sage’s concerns about becoming the breadwinner in her relationship as Diego plans to become a full-time author. As the tension between the pair builds, they begin to suspect this may not be a straightforward double-booking after all.

When they come, Bone Lake’s twists reveal a plethora of clues laid from the film’s first act, making it both an enjoyably infuriating and rewarding rewatch. What is almost a quirky European love dramedy for most of its runtime touches on some complex subjects and really builds on the cringe-inducing clash between the relatably more private couple and the inhibition-free Will and Cin.

When the revelations come—in a brilliantly handled time-shift—things move quickly into a gloriously tense bloodbath with some memorably visceral gore. Both parts of Bone Lake hold up, offering something for most horror fans to enjoy, from the cringing build-up and closing bloodbath to dark secrets and some unexpected taboos. While the main film may not match up to an opening that has an arrow sail through a particularly sensitive part of male anatomy, there’s no doubt that Morgan’s film masterfully manages to walk a fine line between anxiety and comedy.

Bone Lake has a fine line of quirky comic horror that helps bounce viewers’ loyalties among the protagonists. Some superb, emotional manipulation and unexpected shifts will likely keep them guessing. It’s hard not to feel for Sage and Diego, who have some well-developed issues to work through before they even arrive at the lake. They may be duller and more prudish than Will and Cin, but Sage and Diego are emphatically normal. As various temptations come up to test their relationship, Morgan keeps us on their side, even as the divisions between the two widen, helped by excellent performances from Hasson and Pigossi. A particular highlight is Pigossi’s Diego—it’s gruelling to see his efforts to please Sage, whom he clearly adores, continually undermined.

Of course, this house of mystery and horror may be just the thing to save or break them, but Morgan chooses a wonderfully downbeat and ambiguous moment of catharsis to end the film. In all, Bone Lake is a confident, surprising horror packed with little details and some deft directorial touches that might just make you squirm but will likely keep you entertained.