It Follows (2014)

For 19-year-old Jay, fall should be about school, boys and weekends out at the lake. But a seemingly innocent physical encounter turns sour and gives her the inescapable sense that someone, or something, is following her. Faced with this burden, Jay and her teenage friends must find a way to escape the horror that seems to be only a few steps behind. While celebrated as a modern horror masterpiece, *It Follows* earns its place on a list of best mysteries because its terrifying premise is built entirely around an unsolvable case. The film presents its characters—and the audience—with a paranormal threat that has no clear origin, motive, or identity. The central mystery is not a "whodunit," but a terrifying "what-is-it." Jay and her friends are forced to become amateur detectives, desperately trying to understand the rules of the curse they're facing: How is it passed on? What can it look like? And most critically, how can it be stopped? The film masterfully withholds easy answers, forcing its protagonists to piece together clues from their own horrifying experiences, making the investigation into the nature of the entity the very engine of its suspense and dread.