Director Daniel Stamm’s new movie Lockbox adapts the acclaimed Knifepoint Horror podcast into a feature-length nightmare. Produced by Capstone Pictures (Obsession), the movie sees The Haunting of Hill House star Carla Gugino as a woman fighting to protect her veteran cousin, played by Lou Taylor Pucci (Evil Dead), from a demonic presence linked to her mysterious neighbor, portrayed by Katharine Isabelle (Backrooms)
In an interview with Digital Trends, Stamm, Pucci, and Isabelle discussed collaborating with each other and Carla Gugino in taking a popular podcast and turning it into an unsettling and unpredictable horror film.
This transcript has been edited for length and clarity.
Digital Trends: Tell us what makes [Lockbox] so unique as a horror movie.
Stamm: What makes it so unique…is that it is not a copy of a copy. It’s not like, “Oh, it’s a version of The Shining or it’s a version of The Exorcist…” It’s fully and unapologetically its own story. It’s based on a podcast by a genius writer called Soren Narnia, who is basically Stephen King [but] slightly darker even and who just has a million ideas that he’s not precious about, so he just puts them out and doesn’t linger on them.
Digital Trends: I want to learn more about how you approach adapting this podcast for the big screen. I know it can be an unusual thing to adapt for feature films, so can you tell [us] more about your process for this?

Stamm: Well, that would go more to the writers, because that’s where the big challenge lies. Because this podcast…is very internal and it’s very much the POV of the protagonist that is basically an internal voiceover. So it’s a nightmare scenario, of course, then to have to do that as film. And I think that’s where you can either succeed or fail.
And Justin Yoffe here, the writer, and Kearie Peak, our producer, they had worked on it for years, I think, before they sent out the script and really nailed it…I hope that if you didn’t tell anyone that this was a podcast once, you would never think it from watching the movie, and that was kind of our goal with it: that it feels very natively like the movie it wants to be.
Digital Trends: Right. And going back to what you said about the protagonist’s point of view. Actor Carla Gugino, she plays the lead character in this movie. She tries to save her cousin when all sorts of supernatural occurrences are going on. What was it like collaborating with her on this project?

Stamm: Carla is kind of incredible in that she is not only a fantastic actress…but she’s also the smartest person you’ll ever meet. And this could go either way. It could be a nightmare, or it could be a blessing. She is seeing everything in every department.
If the prop department grabbed a prop that is a slightly more shade of green than the curtain that I wanted it to play with, she will see things that I don’t even see, which is daunting as a director. But also, what a blessing and what a help…Other than that, she would never comment on other actors’ performances. She’s very respectful of that.
Digital Trends: Amazing. Lou, Katharine, what appealed to you so much about the story of Lockbox?

Pucci: I like that it was kind of a roller coaster. You don’t know where you’re headed, and you get this setup. This lovely woman, Carla Gugino, who’s basically playing herself because she’s just so sweet of a person. And she takes in this lowly cousin who has maybe mental problems. Everyone’s telling her it’s going to be difficult to have him. But he’s family. And…it all kind of surrounds this murder mystery.
So it becomes a little bit of a courtroom drama, and it becomes a little bit of a supernatural horror, but we really don’t know what’s gonna happen next. And so the surprises that kept coming [made] me more interested in that script, and it makes me like the movie a lot.
Isabelle: I think, selfishly for me, just the character of Vahna, which was the first experience I had with the script. I only get some audition sides. I have no idea what movie it is or what it’s about or [what] genre [it is]. Nothing.

She was just such a great character. She was so kooky and charismatic and manic and dangerous and vulnerable and adorable and funny all at the same time. It was like, “I don’t care what movie she’s in. I want to be her.”
It was just, overall, such a pleasure to attach myself emotionally to this character that I loved, and then find out the whole world behind her.
Digital Trends: Lou, I [also] want to hear more about how you approached bringing your character to life.

Pucci: I mean, he’s got a really troubled, complex sort of personality, and he goes through so much in the story…Daniel and I had to bring him to life in some ways, because as I’ve been explaining, we didn’t know how evil we wanted to portray him or how good we wanted to portray him.
So every time that I had a chance to do at least two takes, one would be a little bit more innocent, and one would be a little bit more aggressive or evil, so that Daniel could go in there and choose which scenes we wanted him to seem a little more scary or a little bit more innocent for the audience.
So I had to find a mix between that that I could live with, but that my visual would work for both. And for me, it said in the script he’s emaciated, he’s very military, so I just clung to those things and said, “Okay, that’s what I’m gonna [do], lose as much weight as I can. I’m going to get as buff as I can, shave my head.”
And I’m gonna look in the mirror and see this military guy and play this extremely quiet person, which is a huge challenge, because that just means that you have to create such a rich backstory…to tell a story without your mouth saying anything.
Digital Trends: Absolutely.
Stamm: I just want to add how huge that actually is because, obviously, a big thing between actors and directors [is] always the trust thing…So, for Lou to say I’m okay and open and confident with giving two different performances, and trusting you to make the right decisions in the editing room, is huge for [the] director. It’s a rare, huge vote of confidence that I could not be more grateful for.
Lockbox premieres in theaters on July 3.