The synopsis: A group of female spelunkers become trapped after the cave they're exploring collapses, leading to the horrifying discovery that they aren't alone — they're being hunted by pale, humanoid creatures thirsty for blood.
The twist: The film has two endings, and the original European conclusion is a total punch to the gut. One of the girls survives and starts driving away from the horror of the caves, only to realise that she's hallucinating, still trapped, and will soon die at the hands of whatever is lurking down there. It's depressing as all hell, but also the perfect punishment for someone who ever thought spelunking in some unknown cave formations was a cool way to spend a weekend.
The amount of damage it'll do to your psyche: 🔪🔪🔪