Beware Boiuna Review: A Giant Snake Gets Its 'Lake Placid' Moment in a Fun Thriller

Monster movies are part of the fabric of the horror genre, especially when we make a real-life creature larger than life. While we have done it before, with movies like Lake Placid and Deep Blue Sea, there is something about Mike P. Nelson’s new film, Beware Boiuna, that makes this something more than just another big animal film.

Alli (Jessica Rothe) and Lena (Kiana Madeira) are two women in the Amazon whose lives are thrown into disarray because a giant snake from Brazilian mythology is coming for her revenge. The two find themselves fighting for their lives in a way that only works because Nelson makes sure that his characters have lives outside of the action.

More often than not, these monster movies throw their cast into the mix of things without ever thinking about who these people are before a big animal tries to kill them all. Beware Boiuna allows you to care about its characters and hope that they find a way out in the same way your slasher film would.

Boiuna, a giant snake said to shapeshift and sink boats, features in legends about how Amazonian riverbeds were created. Nelson uses the lore to draw us into Boiuna’s world as we watch Alli and Lena find a way to honor the large snake while trying to make it out alive. Even when Beware Boiuna feels like another monster movie, it still has elements that make it stand out as something special.

Snake Girl Power

We’re not exactly new to a female animal being the aggressor. Famously, every dinosaur in Jurassic Park was engineered as a female. But the themes of female rage present within Nelson’s film make this stand out as more than a story about an animal trying to just attack people. That, in itself, makes these kinds of movies less than stellar: Why is the animal the villain when it is simply trying to survive? But within Beware Boiuna’s 104-minute runtime, the film makes it clear that this is Boiuna’s jungle and respects that.

Trying to survive doesn’t make her the villain; it just makes the characters fighting to get out survivors. But it is refreshing that most of what Boiuna does isn’t really villainous. She’s just living her snake life and doing what she’s been doing for centuries. To invade her space means that you’re putting yourself in harm’s way. That’s just the way it is with Boiuna, and it does kind of rule.

More than that, the relationship between Alli and Lena is rooted in their need to survive both the creatures lurking in the dark (men) and the big snake hunting them all. That makes this a story all about a woman’s instinct to survive. And it’s also what elevates the entire film.

It is hard not to compare Beware Boiuna to its predecessors, many of which have similar beats and situations. But Nelson and company made sure that their snake monster film allowed its characters to learn from the jungle and respect the creature living there.

Maybe it will inspire more of these animal monster flicks. But if it doesn’t, we at least have Beware Boiuna to show us how we should develop horror movie characters. Gone are the days when a character comes in, dies, and we barely know their name. Now, one of Nelson’s movies gives us a beautiful backstory so we care when a giant snake kills someone (even if it is justified).

Beware Boiuna arrives in theaters on October 2, 2026.