Case File to Cultural Memory is a data-visual monograph that examines how true-story horror films transform real events into cultural narratives over time. Using a curated dataset of 52 films and a focused subset of 15 true-crime adaptations, the project introduces original frameworks: including the Narrative Re-framing Matrix and the Narrative Distance Index (DDI) to measure degrees of embellishment, mediation, and narrative drift. Through comparative visual analysis, the project reveals how horror increasingly shifts from case-based retellings toward broader expressions of cultural fear and social anxiety. The work positions horror cinema as a site where collective memory is shaped, distorted, and reinterpreted rather than simply retold.