‘Undertone’ Filmmaker Ian Tuason Learned from All Your Favorite Horror Films to Make His Creepy Hit — but Not in the Ways You Might Expect

Personal? Oh, Ian Tuason’s festival horror hit “Undertone” is definitely personal to him. The filmmaker not only shot the film inside his own house, but wrote some of its deeper emotional elements from his experience care-taking for his parents in that same house. Oh, and star Nina Kiri’s character Evy? She’s working through some of her fears and problems by podcasting, just like Tuason did during that period of his life.

But that doesn’t mean that the first-time feature filmmaker didn’t also approach his chilling haunted house offering without an intellectual bent, too. At Sundance, Tuason and stars Kiri and Adam DiMarco (who is only ever heard in the film) visited the IndieWire Studio, presented by Dropbox, to chat about their film, which was a smash at Fantasia last year and was subsequently picked up by A24, who will release it in theaters this March.

“I kind of studied a bunch of horror [films],” Tuason told IndieWire about the influences on his script. “And I saw a formula, kind of a rhythm, to the number of creepy parts … leading up to a scare or leading up to nothing. I remember color-coding my script. If it’s highlighted green, it’s just a creepy part, like a light turning on. And then if it’s a blue part, it’s a scream, right? … A scream, something like a jump scare. And I just made sure that the rhythm was the same as these other movies.”

The movies in question? Per Tuason: Oren Peli’s “Paranormal Activity,” Eduardo Sánchez and Daniel Myrick’s “The Blair Witch Project,” William Friedkin’s “The Exorcist,” Ari Aster’s “Hereditary,” and Jennifer Kent’s “The Babadook.” Through his research, Tuason broke down a pattern and ratio between those “creeps” (the kind of stuff that just gets under your skin) and screams (something that might actually make you yell in your seat).

“I even have a document of the number of scares,” he said. “[A document of the] ratio between creeps and scares, for all those movies. And it’s really interesting, because ‘The Exorcist’ has the least creeps and scares. And then something like ‘Hereditary,’ the ratio between creeps and scares was so huge, it was like in the double digits of creeps, but there was only like five or six scares. So I just wanted to do it that way.”

The film follows Evy as she cares for her dying mother (Michèle Duquet) in the house she grew up in. Her only real contact with the outside world is care of late-night podcasting sessions with her long-time friend Justin (DiMarco). The pair run a horror podcast, with Evy serving as the skeptic and Justin generally believing most things, but when they are sent a series of increasingly spooky audio recordings that seem to follow a couple in major peril, what they hear starts to take terrifying shape in Evy’s own home.

Watch the complete conversation with the “Undertone” team in the video above.

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