A group of boyhood friends in the summer of 1977. An annual rite of passage in a dark and alluring Pennsylvania wood. The channeling of a malevolent Presence. And a childhood game about to go terribly wrong.... Two brothers in the summer of 1995, reunited by the unspeakable nightmare of their past. A bewitching tavern proprietress and psychic intuitive from New Orleans. The revelation of an apocryphal prophesy.

The Summer of Love has been replaced by the Summer of Fear as a sadistic killer prowls the streets of San Francisco. Known only as 'The Gemini,' his brutal murders have the city paralyzed in a merciless grip of terror as he taunts police with a series of cryptic puzzles and the body count rises. As detectives work to unravel the Gemini's chilling clues, the line between nightmare and reality begins to blur when Cassie Kennedy—a newly separated young mother and part-time psychic—discovers that her dreams are foretelling the gruesome deaths of three women.

1967: A brutal murder occurs at the Weston State Hospital in West Virginia. To amateur exorcist, Merle Blatty, this shocking story rings of the occult. Fueled by a desire to avenge the deaths of his wife and son, Merle investigates the case, unknowingly stepping into a sinister web spanning decades.

In the summer of 1994, psychologist Daniel Hill buys a rustic farmhouse nestled in the rolling hills of West Virginia. Along with his wife and teenage daughter, the family uproots their lives in Ohio and moves south. They are initially seduced by the natural beauty of the country setting. That soon changes when they discover a hidden room in the basement with a well, boarded shut and adorned with crucifixes. Local legends about the previous owner being an exorcist come to light, but by then, all Hell has broken loose.

It takes a survivor to know a madman. When the police need to crawl inside the mind of a monster, they call Caroline. As a child, Caroline was abducted along with her twin sister. Caroline escaped. Her sister didn’t...But there’s something different about her latest case. Something familiar. Teenage girls are being murdered, their organs removed. As the scope of horror widens, Caroline begins to experience blackouts of lost time and disturbing hallucinations that are leading her to one terrible, impossible conclusion.