Note: The following contains spoilers.
One of the cave-dwelling monsters in The Descent attacks and scares the main group 56 minutes into a 96-minute movie. It’s a long time for the “villains” of the movie to not be active in terrorizing the main characters, but Neil Marshall masterfully builds tension throughout the first hour, and by the time the crawlers show up they’re ready to kick the movie into the highest gear possible and not let up. But this first scare almost feels like it shouldn’t work. It should feel so much more telegraphed. The scare comes when we’re from the perspective of the camcorder one of the characters brought, and as soon as you go into that POV you know that a jump scare is coming. It’s just one of those things that triggers the “oh, bad thing is gonna happen” part of your brain.
Yet it still works insanely well because of a few things. Right before the monster shows up, one of the girls is desperately screaming for help. Horror movies have more or less forced us to know that jump scares can only happen at quiet moments, so that there can be an abrupt contrast that leads to the “jump” part. Ironically, the character pleading in the dark for help subconsciously sets our minds at ease. If it isn’t quiet, nothing can startle us. But there’s a beat, just as short a beat as you can have, before the crawler shows up when things go almost quiet. And then BAM the crawler appears and the music cue hits and I scream in my room like a little kid.
That’s what great on the sound design front. On the visual side, when we’re in the camcorder POV the character holding it moves mostly side-to-side, but also slightly up and down. As the aforementioned character is screaming, we start right, pan left, then pan back right and tilt just slightly up. The upwards tilt changes the lighting in the scene so that just as the screaming stops that crawler is barely lit. We have the quiet beat and the camera tilts back down, and the crawler is in clear focus and the scare hits perfectly.