Movies that leave quite an impression on your brain, but not necessarily in a positive way.
http://www.ranker.com/list/scarring-disturbing-movies/but-chickens-double-d,
Deliverance
Misery
Pan's Labyrinth
Paths of Glory
Pet Sematary
The Evil Dead
The Exorcist
The Hills Have Eyes
The Wicker Man
The Vanishing