You’re sitting in the movie theater; it’s pitch black except for the dim glow of the screen. Nothing scary has happened yet—but you see a person walking, alone. You feel an overwhelming sense of dread. There’s a slow, growing hum over footsteps, and you know the person isn’t safe. You, perhaps, feel you aren’t safe watching.

You wait for the inevitable conclusion, fixed on what you might see, listening for the cue that a killer or monster is ready to attack—though nothing on screen hints at this. The source for your anxiety is elusive, but it was carefully crafted through hidden audible elements that play on human emotions, causing your hairs to stand on end. This is the brilliance of what music does in a horror film.

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