This is based on opinion. Please don't list it on a work's trope example list.
Nightmare Fuel / The Devil's Advocate
Good Lord, it's everywhere. Most notably when Kevin's wife goes out with the business partners' wives and finally sees that they are actually demons in disguise. And the baby playing with the ovaries. If that's not enough, there's always every single facial expression Al Pacino has in this movie.
The scene where Mary Anne snaps and commits suicide by slicing her throat with a piece of broken glass.
Her gradual breakdown leading up to her suicide as a whole can be considered this.