Horror films frequently employ psychological and visual techniques to exploit the limitations of human vision, creating moments of fear that resonate deeply with audiences. The article explores how directors and cinematographers intuitively understand visual perception to craft scenes that exploit inattentional blindness and change blindness. Inattentional blindness occurs when viewers fail to notice something obvious because their attention is focused elsewhere, as seen in the film ‘Hereditary’ where the possessed mother appears on the ceiling without immediate recognition. Change blindness, where viewers miss subtle changes in a scene, is also utilized, such as in ‘The Conjuring 2’ where a character’s appearance shifts dramatically during a conversation. The article explains how techniques like eyeline matching, where the camera follows a character’s gaze to direct the audience’s attention, mimic natural human visual behavior to build tension. Wide shots, like in ‘It Follows,’ force viewers into a visual search, scanning for threats that may not be present, thereby heightening anxiety. The piece also discusses how peripheral vision, which detects motion but lacks detail, is used to create unease when something moves at the edge of the viewer’s field of vision. Additionally, the article touches on pareidolia, the human tendency to see faces in ambiguous patterns, which horror films exploit to create unsettling imagery, as seen in ‘Midsommar’ where tree patterns resemble faces. By understanding and manipulating these visual perception mechanisms, horror filmmakers craft experiences that tap into fundamental aspects of human cognition, making the scares more effective and memorable. The article emphasizes that these techniques are not accidental but are carefully designed to exploit the gaps between what is seen and what is consciously perceived, creating a unique psychological experience for the audience.