'undertone' review: A24 Horror Thriller Weaponizes Our Imagination

A slow-burning mystery that eventually crescendos into a nightmarish audio experience from Hell, director Ian Tuason’s undertone is designed to rattle you. It’s a film that turns your creativity and imagination against you; one of those rare horror films that you don’t passively watch but actively experience. Tuason and his crew know that whatever you can imagine is probably scarier than anything that’s explicitly put on screen. All he has to do is provide the catalyst for the viewer to muse on something unsettling — which undertone has in spades — prompting you with its chilling use of negative space, creeping zooms, and immersive sound design, which will be ringing in your ears long after its riotous final setpiece, and let your mind do the rest.

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