Keep in mind — these responses have spoilers and discuss some graphic content. Here's what people said:
1. "The scene in the original Pet Sematary, where the old guy gets his Achilles tendon cut from the little kid under the bed. I always checked under the bed after that."
4. "The dip scene in Who Framed Roger Rabbit? is so fucked up. There is something about murdering an innocent cartoon shoe that makes it so much more disturbing than your average Hollywood murder scene."
11. "The basement scene in The Road. Looking at his pistol's load-out because he might have to shoot his son because of cannibals. Fuck, what a nightmare for a father — just had my son shortly before that movie and it scarred me to the point where I told my brother to not bother watching it. Dismal, gray movie from beginning to end."
13. "In Mirrors — the plot is basically there's another dimension in anything reflective. A woman looks at her reflection in the mirror before getting in the bath. As she leaves the mirror, her reflection remains there. Couple of minutes later, she's chilling in the bath and the mirror version of her just starts ripping its own jaw open, which in turn forces the woman's jaw open in the bath, and she cannot do anything about it."
14. "The scene in Earnest Scared Stupid, where the girl checks under the bed and finds nothing, then rolls over in bed and the troll is right fucking there. To this day, I do not roll over in bed — if I want to lay on the other side of my body, I flip around so my head is at the foot of the bed instead of rolling over to face the wall."