Mike P. Nelson almost didn’t make Beware Boiúna. When the producers came to him with a giant snake movie, his first answer was no. “There is a lot of stigma behind giant snake movies,” he told us, and he knew it would be an uphill battle where he could never make everybody happy.
So they asked him how he would do it. His answer turned into the movie, and it came down to one question he kept asking himself:
Could I make a giant snake movie that actually feels scary and has some level of dread to it? Because I can’t say that I’ve seen one before that does that.
We sat down with Mike for the second time on Grave Tone, and the more he talked, the more it sounded like a playbook. If you love creature features, or you’re a filmmaker dreaming of making one, these are the rules he followed. No spoilers, promise.
Beware Boiúna (2026)
Directed by Mike P. Nelson · 104 min · R
Beware Boiúna drops a group of doctors into the Amazon, right where an ancient giant snake has decided she's done sharing her home. Mike P. Nelson directs Kiana Madeira, Jessica Rothe, and Logan Marshall-Green in a creature feature rooted in local folklore and shot on location in Colombia, with real explosions, real stunts, and nobody guaranteed to make it out.
Rule 1: Hold Back the Creature to Build Dread
Mike went straight to the masters for this one.
You look at Alien, you look at Jurassic Park, you look at Jaws, you look at Tremors for that matter.
He said, and what he studied was how those films built suspense before finally showing the creature. He was just as interested in the creativity of the moments when they didn’t show it.
That’s the difference between a monster movie and a scary monster movie. A giant snake on screen for two hours is a spectacle; a giant snake you’re waiting for is a threat. Mike wanted the second one, and that choice is what got him excited enough to say yes. “It seemed like a lot of fun,” he said.
And then it was like I was selling myself on the idea.
Think about the last creature feature that actually got under your skin. We’d bet it made you wait.
Rule 2: Make It Feel Like Two Movies in One
His biggest comp wasn’t even a creature feature. It was William Friedkin’s Sorcerer, one of Mike’s favourite movies, and he loves it for its structure.
It’s one movie at the beginning and one movie at the end.
In Sorcerer, you meet a bunch of characters, you learn what they’re dealing with, and you see a tense backdrop of civil unrest where the locals are fighting against the man. Then, suddenly, the rest of the movie is those guys transporting nitroglycerin through the jungle, where one wrong move means they’re dead.
Mike’s pitch for Beware Boiúna was basically that, swapped out.
Except for explosives, it’s a giant snake. And except for people on the lam, it’s a bunch of really good doctors.
It works. Halfway through our screening, something happens (we’re not saying what) that had Arthur thinking, “Wait a minute. This is a different movie now.” Meaghan put it simply:
It starts one way, and then it kind of turns into something else later on.
We were pleasantly surprised, and that’s the whole point of the rule.
Listen to the full episode:
Rule 3: Make Sure Nobody Feels Safe
When we played our fill-in-the-blank game, Meaghan gave Mike this one: “Every creature feature needs at least one…” Mike called himself “a classic overthinker” and said these games are the worst for him. Then he nailed it anyway:
Every creature feature needs a character who doesn’t deserve to die.
That idea runs through the whole film. The snake doesn’t care who she eats. Healer, poacher, anyone in between. Meaghan said it’s what makes the story more interesting, because:
You never quite know who’s safe.
There’s no moment where you can relax and think a character will be fine, and we saw that happen multiple times.
The early promo showed Boiúna swallowing viral internet animals, which Arthur found hilarious. Mike called it a misdirect that asks a question:
Yes, you are going to have some fun, but what kind of fun?
Is it also going to be a little mean? His answer: “We’re not gonna spare cute little animals.” Meaghan pointed out it almost works as foreshadowing, and Mike agreed right away.
Rule 4: Give Every VFX Monster Something Real
This is the rule practical effects fans are going to love.
If I’m gonna have a VFX snake in my movie, there has to be something real that goes along with that VFX snake.
So they didn’t take the easy way out. When a stuntman gets yanked 40 feet into the air in the middle of the jungle, that was a real stunt team with real ropes, and all the foliage blasting out happened in camera while the actors were right there. “It’s like, no, we got a stunt team in there,” Mike said. No digital double.
The lumber camp structure collapsing? They set off TNT while the leads ran down the ramp, so the boom they reacted to was an earth-rattling explosion. When a character gets chomped by the snake, they blew up the floor with explosives. “Anything that we could do physically to make it feel real and reactive to everybody on set, we did it,” he told us.
Did it safely, but we did it.
Meaghan pointed out the payoff: it makes the reaction easier for the actor, and you get authentic reactions out of everybody. Kiana Madeira, who plays Lena, spends a big chunk of the film wet, muddy, and covered in viscera. Mike called her “such a trooper.“
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Rule 5: Let Your Actors Play
Mike is not precious about his script. The only time he sticks to the page is when a line is tied to an important story beat that has to land later. Otherwise, he wants his performers to find things.
“The more you allow them to play, the more it surprises you,” he said.
And if it’s surprising me, it’s going to surprise more people as well.
His favourite example involves Logan Marshall-Green and Jessica Rothe in a heated moment at the bar. Logan could feel when a button needed pushing, and some of the things he said started getting under Jess’s skin. The set went quiet. Everyone wondered if things were okay.
After the take, Logan went up to her and asked, “Are you good? Are you good?” According to Mike, she’ll tell you she was starting to get annoyed; she knew what Logan was doing, so she decided to channel it. Not all of his lines made the cut, but the looks he got out of her did.
Meaghan’s reaction to hearing the story was pretty much ours too: “Oh god, is she actually mad?“
Rule 6: Root the Monster in Something Real, Then Let the Audience Decide
Boiúna isn’t just a big snake. The team found folklore from the area and tied it to a real creature that science found in Colombia, Titanoboa, and Mike got excited about how those two worlds could merge. The film also opens with illegal gold mining taking over the jungle, which he said is “very real right now.” While researching, he saw newsreel footage of Indigenous people and tribes standing up and fighting back.
What he refuses to do is tell you what it all means. Arthur asked whether Boiúna is a hero, the environment’s immune system, or just hungry.
It wasn’t my job to sit there and tell you that this Boiúna is this magical creature or Boiúna is fighting for the forest.
Mike said. Those ideas are in there on purpose, but so is the other side:
It’s a giant snake and they’re hungry.
He loves when movies leave room for that argument. One person says she’s a protector of the jungle, like a god; another says she’s a hungry snake trying to survive. “I love, you know, when conversations can be had,” he told us.
It also meant going to Colombia with open ears. Mike talked to people who had witnessed the mining, and some told him they never thought someone would tell this story through film. What excited them even more was that it would be a genre movie built around a creature from their own folklore. The way he describes it, the whole thing was about keeping your eyes and ears open, listening, learning, and then just jumping in.
Meaghan summed up the result better than we could: Beware Boiúna is a fun creature feature that delivers a relevant message, and a lot of people will walk in expecting a giant snake movie. They’ll get one.
There’s plenty of snake. Beware Boiúna hits theatres on October 2.