In 1993, Dr. Florence Weaver and her colleagues Victor Fields and John Gregory treat a psychiatric patient named Gabriel at Simion Research Hospital. Gabriel has special powers like controlling electricity and broadcasting his thoughts via speakers. One night, Gabriel turns violent and kills several staff members of the institution.
Twenty-eight years later, Madison Lake, a pregnant woman living in Seattle, returns home to her husband, Derek Mitchell, after her pregnancy causes her to feel ill at work. During an argument, Derek smashes Madison’s head against a wall after which she locks herself in the bedroom and falls asleep. Madison later wakes up to find Derek’s body after having a dream of a man entering their house and violently killing him. The killer, still being in the house, attacks Madison, rendering her unconscious.
The next morning, Madison wakes up in a hospital and is informed by her sister, Sydney, that her unborn baby didn’t survive the attack. After being interviewed by police detective Kekoa Shaw and his partner Regina Moss, Madison returns home. That same hour, Gabriel kidnaps a woman running the Seattle Underground Tour. Madison sees another dream about Gabriel murdering Weaver.
During their investigation, Shaw and Moss discover a photo of Madison as a child in Weaver’s house and learn that she specialized in child reconstructive surgery. Madison and her sister approach the police after watching Gabriel murder Fields. Gabriel contacts Madison, causing her to remember her past. She and her sister visit their mother, Jeanne, to learn more. Madison realizes that Gabriel wasn’t her imaginary friend but someone real whom she talked to during her childhood. Shaw finds a link between the doctors and Madison, which leads him to discover Gregory’s dead body.
