A24 is dropping Undertone this Friday, March 13, and if you needed one more reason to pay attention, it’s sitting at 88% on Rotten Tomatoes after 40 reviews. Opening on a Friday the 13th is not a coincidence. A24 knew exactly what they were doing.
The premise is genuinely unsettling. Canadian podcaster Evy (Nina Kiri) is caring for her comatose mother when her co-host Justin (voiced by White Lotus star Adam DiMarco) starts sending her a series of anonymous audio recordings, each one mirroring something terrifying that’s actually happening in her life. The film never leaves its single location. There are only two on-screen performers. And critics are already calling it one of the scariest horror films in years.
Here’s the kicker: the same week a $90 million horror production (The Bride!) bombed at the box office, this micro-budget Canadian indie from first-time director Ian Tuason is the one everyone is talking about. If you’re looking for the best horror movies of 2026 so far, Undertone is making a very strong early case.
What Critics Are Saying
The positive camp is loud. Roger Ebert’s Brian Tallerico called it “a sonic and visual nightmare” that “announces its filmmaker as a major talent,” specifically praising its refusal to over-explain and its chilling final act.
Deadline called it “creepy as hell,” a film that lives in soundscapes that tell you more with your eyes closed than open (honestly, that line alone should be enough to sell you a ticket). Horror Press went furthest of all, calling it A24’s scariest since Hereditary. That Hashtag Show singled out Nina Kiri’s performance as exemplary and praised the film’s sound design as immaculate.
The skeptical side is worth hearing, too. IndieWire acknowledged the craft but said the finished product fails to deliver a conclusion scary enough to justify its slow-burn format. The Hollywood Reporter called it another flagrant Hereditary borrower that loses itself in its influences.
Here’s the thing about those mixed takes, though: even the negative reviews praise the sound design and Kiri’s lead performance. The debate is entirely about the script and the ending, not about whether the filmmaking is accomplished.
For horror fans willing to meet a movie on its own terms, that’s actually an encouraging sign. The craft is not in question. This is a film built for a theater. Big sound, close darkness, no exits. You’ll want to see this on the best A24 horror movies ranked list by the time you walk out.
Ian Tuason, the Paranormal Activity Connection, and Why This Film Matters
Ian Tuason conceived Undertone while caregiving for his dying parents during the pandemic. That grief is not decorative; it’s the architecture of the whole film. Evy’s situation mirrors Tuason’s own, and that autobiographical weight is part of why the film lands as hard as it apparently does.
The festival run is legitimately impressive. Undertone premiered at the Fantasia International Film Festival in July 2025, where it won the Audience Award. A24 acquired it in a seven-figure deal shortly after. It then screened in the Midnight section at Sundance 2026, which is about as strong a festival arc as a micro-budget debut can have.
Now for the piece of information that was largely buried: Blumhouse hired Tuason to direct the Paranormal Activity reboot based on the strength of Undertone alone. That is not a minor detail. A franchise that defined an era of found-footage horror is betting its next chapter on a first-time director whose debut hasn’t even opened in wide release yet. That’s a massive vote of confidence, and it tells you this is not a one-and-done filmmaker.
One last note worth knowing: the theatrical version A24 is releasing is not identical to the film that won at Fantasia. The original cast featured Kris Holden-Ried in the key voice role of Justin; A24 recast with Adam DiMarco after acquisition (a deliberate commercial upgrade the studio clearly felt mattered). It’s a small detail, but it speaks to how seriously A24 treated the project from day one.
Undertone runs 94 minutes, rated R. It opens Friday, March 13. In a month crowded with big-budget swings, it’s a reminder of what A24 built its reputation on: one location, minimal budget, and maximum dread.