In horror, few visual elements are as hauntingly effective as a sinister smile. Certain unsettling grins reveal the duality of human (or inhuman) nature, often masking madness, cruelty, or despair beneath a facade of charm or humor. Whether it’s a predatory smirk meant to intimidate or a ghastly grimace signaling complete psychological unraveling, these smiles have the scary ability to linger in the audience’s mind. The smiles turn moments of terror into unforgettable scenes that define the genre.