The human face is supremely important on a social and biological level. Most of our non-verbal communication comes from reading subtle facial movements, and its importance in our cognitive thinking is best shown in our tendency to see faces in inanimate objects (think of how many times you have looked at a rock face and thought you'd seen two eyes and a mouth). So there is something genuinely disturbing to most people about seeing a face visibly distorted, mutated, or rearranged ... so, naturally, this type of Body Horror is one of the most common Horror Tropes.
A sister trope and effective primary component of Nightmare Fuel.
It is in fact at least Older Than Feudalism — armies the world over have based their war masks around this trope, and in mythology and folklore, just about any self-respecting demon or supernatural evil will have one.
More recently, it has also become a staple of Surreal Horror.
This is a main symptom of Coming Back Wrong. Most humanoid examples of Our Monsters Are Weird will fit this trope.
This trope is commonly doubled with the Jump Scare in a Screamer Prank.
- Black Eyes of Crazy
- Black Eyes of Evil
- Ghostly Gape
- Glasgow Grin
- Glowing Eyelights of Undeath
- The Blank
- Eyeless Face
- Facial Horror
- More Teeth than the Osmond Family
- Red Eyes, Take Warning
- Slasher Smile
This trope's well-meaning (but still scary) sister, the Grotesque Uncanny Valley, which usually ends up here by accident.
Game Face, which comes into play when a supernatural villain disguised as a human flashes his true form's Nightmare Face to scare someone.
Demon Head, cousin to this trope.
This is one theory as to why some people are afraid of clowns. Exaggerated mouths, bulbous noses, and pin-prick eyes are downright terrifying to young children who have not yet figured out that the person is just wearing make-up and not deformed.