For nearly half a century, one eerie sound has been showing up again and again in movies and TV shows. It’s typically used when something spooky or mysterious happens—and it can be heard in Poltergeist, The Matrix, Let the Right One In, and countless episodes of Unsolved Mysteries. So where did this strange sound come from, and how did it spread across Hollywood? This story comes from the podcast Every Little Thing.

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Episode transcript, music, and credits can be found here: https://www.20k.org/episodes/liquidterror

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