A killer is on the loose in first look at horror movie There's Someone Inside Your House

In the Netflix horror film There's Someone Inside Your House (premieres Oct. 6) a killer starts picking off students at a Nebraska high school. The twist? The maniac wears a mask resembling his victims' faces and publicly reveals their darkest secrets for good measure. This adaptation of Stephanie Perkins' novel is written by Henry Gayden (Shazam!) and directed by Patrick Brice (Creep). The slasher movie's cast includes Théodore Pellerin, Asjha Cooper, Dale Whibley, Jesse LaTourette, Diego Josef, and Sydney Park, who portrays student Makani Young.

"Makani is a young woman from Hawaii and she goes to live with her grandmother in Nebraska," says Park. "She's sort of an outsider amongst her outsider friends at her Nebraska high school. We come to learn that Makani is carrying something heavy, we know she has a secret, we just don't know what it is yet. So when all these kids start dying brutally and their damning secrets are brought to light, Makani is under the impression that she's next or that someone knows something."

The actress describes the film's Vancouver shoot as a "grueling" experience.

"I feel like any time you're in a horror film it requires you to really extend yourself and go there in your mind emotionally," says Park, who played the character Cyndie on The Walking Dead. "There were these never-ending days, and I had to constantly cry and cry and cry, and be scared, and build up my angst, and all of these emotions. It was definitely exhausting but it's a part of the thrill. It was really fun and challenging and I had a great team to support me."

Director Brice reveals that author Stephanie Perkins has been encouraging about the project and visited the set.

"Having her support was really important," says the filmmaker. "Henry, the writer, strayed from the novel and took some creative license in terms of making it feel as cinematic as he could. The fact that she was really excited about that and loved the ways that it was different from the novel was a relief because you bear a certain sense of responsibility taking this thing from this one person's head and turning it into a movie. Unfortunately, the day that she arrived, we were filming a scene where Sydney Park's character was being picked up by an Uber driver, so it was about as uninteresting a moment in the movie as you could find. But she was still excited to be there and amazed that it was all happening."

There's Someone Inside Your House is produced by Shawn Levy's 21 Laps and James Wan's Atomic Monster.

"There's Someone Inside Your House is really us, collectively, wanting to go back and do somewhat of a traditional slasher film, like the kind of slasher films we would get from the '80s," says Aquaman filmmaker Wan, whose horror directing credits include Saw and the just-released Malignant. "Today's generation of kids don't really have all the kind of cool stuff that we grew up with. I mean, they have other cool stuff, I don't feel sorry for them, but I wanted to introduce them to all that fun stuff that we grew up with and this really is something of a [flashback] to that era."

Brice has already sequelized one of his films with 2017's Creep 2 and admits he and writer Gayden have tentative plans to continue the story of There's Someone Inside Your House.

"Yes, Henry and I are cooking up sequel ideas as we speak," he says. "I think we landed on one that expands on the characters and the themes of the universe and also weaves in some contemporary issues. We're definitely talking about it. Fingers crossed, enough people watch this. But let Netflix know that we're ready to have that conversation."

Exclusively watch the trailer for There's Someone Inside Your House above and see first look images from the film above and below.

Want more movie news? Sign up for Entertainment Weekly's free newsletter to get the latest trailers, celebrity interviews, film reviews, and more.

Related content:

• The best horror films of 2021 (so far)
• How Attack the Block became a monster hit at SXSW
• The Night House director David Bruckner's life in horror