Frederick Fitzell's (Dylan O'Brien) idyllic life is turned upside down when he starts having disturbing visions of Cindy (Maika Monroe), a missing girl he knew in high school. In an effort to control the horrifying episodes he is experiencing, he reaches out to his friends with whom he took a mystery drug called Mercury. Soon, he realizes that in order to finally put an end to his dilemma, he must go on a terrifying journey deep into his own memories to discover the truth. Written and directed by Christopher MacBride.