Have you ever wanted to go on an adventure in the Amazon? Welp, the latest of new horror movies, Beware Boiúna, might change your mind. In a similar vein to 1997’s (highly rewatchable) Anaconda, this new film about a group of people who find themselves terrorized by a big snake while in the South American rainforest. But, one especially nasty scene has nothing to do with fictional snakes. It’s about a real bug that can literally get under your skin, and CinemaBlend found out how the moment was pulled off.
When CB spoke to Beware Boiúna director Mike P. Nelson about his tastes regarding gross-out moments, he pointed to the making of one memorable scene. In his words:
You’ve now twisted my arm to talk about, which will hopefully be one of the standout sequences of the movie that doesn’t even have a giant snake, which is the botfly extraction. It was one of the most fun moments to shoot. You know, Jessica [Rothe] was doing that all on her own. She was really pulling those things out of a prosthetic effect that we placed on our actor Will Close’s back, and she really dug in there and pulled these prosthetic worms out, and she got nice and close.
A botfly belongs to a family of flies whose larvae live as internal parasites of mammals, and I’m shuddering even thinking about it. Anyways, in Beware Boiúna Will Close’s Callum gets some in his back and Jessica Rothe’s Alli extracts them out of him. As Nelson shared, the scene was accomplished practically. The filmmaker added:
We had tubes running up the back. I had I believe three different types of liquid: like a pus, something clear, and then a blood. And then, we had our special effects team on the side with syringes as she was pulling it out, squeezing a little bit of blood, then a little bit of pus, and then like a little bit of something thicker that kind of oozed out.
Eww! But, that’s kind of the point though right? Nelson and co. deserve a lot of credit for pulling off such a scene using practical effects, though. The director also said this about deciding to have the scene in the film:
I fucking love that stuff! And, when I found out that this bot fly thing was a real thing, and not just in the Amazon, like this is something that can happen anywhere in the world, it left a taste in my mouth that I was like, ‘We’re putting that in this movie. And, I know if it’s going to affect me that way, I’m like, I have to put this in a movie.’
What’s also unsettling is that Botflies are much more common than giant snakes, so people may really want to watch themselves if they’re venturing into the rainforest. You’ll mostly find them in specific tropical regions like Central and South America like where the team on the humanitarian medical mission is in Beware Boiúna.
Of course, though, the main creature in Nelson’s movie is a one-hundred foot long mythical serpent who’s famously talked about in Amazonian folklore. It’s depicted in this new film as a terrifying force of nature that seeks to protect the jungle.
Not only is the film led by Jessica Rothe (who recently shared a Happy Death Day 3 update), but it also stars Kiana Madeira from the Fear Street trilogy and another horror mainstay, Upgrade’s Logan Marshall-Green. Beware Boiúna is Mike P. Nelson’s fourth feature film following 2018’s The Domestics, 2021’s Wrong Turn and last year’s Silent Night, Deadly Night, each of which dwell within the horror genre. And he’s not leaving the genre as he’s been hired to make the next Saw movie with Blumhouse and Atomic Monster.
You can check out Beware Boiúna in theaters now. And, horror fans, it’s the perfect time to check out the 2026 movie schedule given so many are coming out this month.