Yellowstone Star’s New R-Rated Horror Movie Officially Breaks 8-Year Rotten Tomatoes Streak

Published Oct 2, 2026, 10:45 AM EDT

Grant Hermanns is a TV News Editor, Interview Host and Reviewer for ScreenRant, having joined the team in early 2021. He got his start in the industry with Moviepilot, followed by working at ComingSoon.net. When not indulging in his love of film/TV, Grant is making his way through his gaming backlog and exploring the world of Dungeons & Dragons with friends.

The Logan Marshall-Green-starring Beware Boiúna is officially dividing critics on Rotten Tomatoes.

Hailing from rising horror director Mike P. Nelson, the R-rated thriller centers on a group of humanitarians venturing deep into the Amazon rainforest to deliver medicine for those in need, only to find themselves hunted by the titular, colossal mythical serpent. Alongside the Yellowstone universe vet, the film's cast includes Fear Street's Kiana Madeira and Happy Death Day's Jessica Rothe, with Nelson directing a script from Star Trek alum Alan B. McElroy.

Now, as the horror movie makes its way to theaters, reviews have rolled out for Beware Boiúna, netting it an official Rotten Tomatoes score. With 34 reviews at the time of writing, the film holds a "Rotten" approval rating of 56% from critics, pointing to a very divided response from reviewers. More notably, it also breaks Nelson's eight-year streak of Fresh ratings from critics on the review aggregate, marking his first Rotten score in the director's chair.

Ever since making his feature directorial debut with the post-apocalyptic horror film The Domestics, which still holds a rare perfect 100% approval rating on Rotten Tomatoes, critics have generally been in favor of Nelson's work behind the camera. His work on the Wrong Turn reboot left some divided, but still narrowly netted it a Fresh score, while his recent Silent Night, Deadly Night reboot became the best-reviewed of the series. Check out his Rotten Tomatoes scores in the chart below:

Title	Rotten Tomatoes Critic Score	Rotten Tomatoes Audience Score
The Domestics (2018)	100%	50%
Wrong Turn (2021)	64%	59%
V/H/S/85 (2023)	75%	64%
Silent Night, Deadly Night (2025)	76%	77%
Beware Boiúna (2026)	56% (as of 10/2/26)	TBD

Despite the initial disappointment of a Rotten rating, it is worth noting that Beware Boiúna's streak-breaking Rotten Tomatoes score doesn't entirely spell bad things for the film. For starters, given how often scores fluctuate, there is a very real chance the horror movie could slide its way back up to the Fresh side of the scale, considering how close it is. ScreenRant's own George Bate was partly mixed in his Beware Boiúna review, which secured a 6/10 score, but still positively compared it to Steven Spielberg's Jaws:

Like Steven Spielberg’s approach to his killer shark, Nelson understands that less is more when it comes to crafting an effective creature feature. Rather than flood his film with on-screen carnage and numerous wide shots of the snake, he opts to keep Boiúna in the shadows, amid the obscurity of the jungle. This level of restraint means that, when Boiúna does pop up fleetingly, the terror of the characters becomes the audience’s, as, until that point, viewers were left to fill in the gaps of what Boiúna looks like and how big it truly is with their imaginations. When Boiúna does slither onto the screen more prominently, the giant snake is quite the sight to behold. The quiet, calculated menace of the pitch black creature evokes memories of Ridley Scott’s Alien, while the action-packed climax has more than a few references to James Cameron’s Aliens.

Additionally, when it comes to the horror genre, particularly that of snake-based horror movies, audiences often end up on the Fresh side of scale. The Paul Rudd and Jack Black-led meta Anaconda reboot is key proof of such, as the film left critics split with its 48% approval rating, while audiences were much more appreciative of its tongue-in-cheek comedy to give it a 74% score.

Regardless of where Beware Boiúna cements itself on Rotten Tomatoes with critics and audiences, Nelson already has a bright future ahead of him, having recently been tapped to helm the next Saw movie at Blumhouse. With the filmmaker also previously teasing hopes to develop a sequel to his Silent Night, Deadly Night reboot, and getting a proper stab at Friday the 13th after his Sweet Revenge short, his new film's success and that of Saw's could further propel him to fulfilling those goals.

Cast

• 

  Logan Marshall-Green

  Brennan Malloy

• 

  Kiana Madeira

  Uncredited

A medical mission in the Amazon becomes a struggle for survival against the Boiúna, an ancient predator protective of its domain.