For many years, Heather Mason (Adelaide Clemens) and her father, Harry (Sean Bean), have been on the run from dangerous forces she does not understand. Heather continues to be plagued by terrifying nightmares and frightened by her father's disappearance, and on the eve of her 18th birthday, she discovers that she is not who she thinks she is. The revelation leads her deep into the demonic world of Silent Hill, where she may become trapped forever.