What happens when a medical mission encounters something far more dangerous than it ever anticipated? That’s the setup for “Beware Boiúna,” a new horror thriller in which a group deep in the Amazon comes face to face with Boiúna, the mythical Brazilian serpent—and quickly discovers they are dealing with a predator unlike anything they’ve ever seen.
Mike P. Nelson directs the film from a screenplay by Alan McElroy, based on a story by McElroy and Tony Giglio. Nelson recently directed the 2025 remake of “Silent Night, Deadly Night” and contributed two segments to the horror anthology “V/H/S/85.” McElroy, meanwhile, is a longtime genre veteran whose credits include 2003’s “Wrong Turn” and “Halloween 4: The Return of Michael Myers.”
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A trio of recognizable performers makes up the main cast. Kiana Madeira, Jessica Rothe, and Logan Marshall-Green star in the upcoming film. Horror fans are familiar with Madeira and Rothe thanks to previous roles. Madeira starred in the popular “Fear Street” film trilogy. Rothe portrayed Tree Gelbman in “Happy Death Day” and its sequel “Happy Death Day 2U.” Marshall-Green is currently starring in Christopher Nolan’s blockbuster “The Odyssey.” He can also be seen on the TV series “Marshals.”
The film’s official synopsis:
“Deep in the Amazon, a medical mission spirals into a fight for survival when Boiúna, a colossal ancient predator, awakens to reclaim her domain. In the jungle where nature holds absolute power, she decides who lives and who dies.”
Jeremy Bolt and Robert Kulzer serve as producers on “Beware Boiúna.” The horror film premieres only in theaters on October 2. Watch the newly released trailer below via Lionsgate.
