It Follows is a slow, building burn that will envelop you. This is a horror movie at its finest.
Jay navigates adolescence in her dilapidated town without much help from family. She's not doing a terrible job. Then something strange happens. Somebody—or something—starts to follow her wherever she goes.
In contrast with many a horror flick, the characters' reactions are believable. The story flow, music, and cinematography are masterful.