1. Sleepaway Camp
“That one got me. You’re watching this campy 80’s horror movie and then all the sudden it’s like the ending to a completely different kind of horror movie. That. Was. Terrifying.” — Hysterymystery
2. The Ring
“You know, The Ring has a pretty fucked up ending.
SPOILERS: Her son accidentally watches the tape and she realizes the only way to escape death is to copy the tape and show it to someone else. The curse then passes on to that person. So she helps her son make a copy so he can show it to someone… her son asks her who they’re going to show the tape to…
Roll credits.” — RedditsInBed2
3. The Orphanage.
“I absolutely love this movie because the ending had an incredible plot twist that changed the entire vibe of the movie. Still horrifying and sad, but that ending was… different from any horror movie.” — whatawonderfullearl
“I’ve posted before speaking about the film Martyrs… And I will speak of it again I’m sure. You’d have to be pretty desensitized to not be haunted by the films last bit.” — SmilingFlounder