Ruth and Harry decide to take a romantic backpacking trip through the Pacific Northwest, but amongst the beautiful scenery, Ruth makes an unexpected discovery that sets her off on a strange, frightening new path. The couple aren't alone in the woods, and they might not be the same when they come out...if they come out.
This movie contains 28 potentially triggering events.
Ruth describes her childhood in a dysfunctional family.
SPOILERS
The alien conceals itself as Ruth's boyfriend Harry. After finding out Ruth tries to kill "Harry" by kicking him and pushing him off a cliff. "Harry" comes back and tries to kill Ruth. Even though it's technically not domestic violence, this might be triggering to some.
At the beginning of the movie a deer is Stocked by something and killed. Then at 22:45 the girl walks up on the deer to find its head split in half an it’s body covered in something. It does quite a few close-ups so if you want to skip it completely skip to 24:17.
The head squashing yes, but the rest is subjective. Blood more than gore. A few characters are bisected vertically, but upon splitting they almost look like printed xrays.