As the hauntings grew more unsettling, Debbie and Camilla were unable to part with the doll and made the desperate decision to contact the Warrens. The Warrens go on to say that the doll was actually a vehicle for a demonic entity that tricked Debbie and Camilla into giving it possession of one of their bodies, rather than being truly possessed.
Near 1971, after a span of three years, the Perron couple, along with their five daughters, Andrea, Nancy, Christine, Cindy, and April, relocate to a farmhouse located near Harrisville, Rhode Island. Sadie, their dog, won't go inside the home. Almost immediately after moving in, Carolyn, Roger, and their five kids noticed odd things happening.
The worst of them all was the spirit shown in the movie Bathsheba.
The oldest of the five girls, Andrea Perron, said of the ghost, "Whoever she was, she felt herself to be mistress of the house and she resented the competition my mother posed for that position." After a small mistake during a game of hide and seek, the boarded-up entrance to an unidentified cellar is found. During the first several nights, there are paranormal activities. At 3:07 a.m., all of the household's clocks stop. Every morning, Carolyn awakens to more noticeable bruises. Sadie is discovered dead in the garden one day. A spirit of evil is encountered by both Carolyn and Christine.
When Carolyn gets in touch with the Warrens, they set up a meeting and decide to carry out a preliminary investigation. Lorraine, who is clairvoyant, observes that the Perron family has been targeted by evil forces. She clarifies that they won't be set free by leaving the residence. With the assistance of their aide Drew Thomas and police officer Brad Hamilton, they set up cameras and bells throughout the house to collect evidence. Subsequent investigation indicates that the home was formerly owned by Bathsheba Sherman, a suspected witch and Mary Towne Eastey's relative. Sherman sacrificed her week-old child to the devil and committed herself in 1863 at 3:07 in the morning after confessing her love for Satan and punishing anyone who stole her land. The houses that were constructed on the land have a history of multiple murders and suicides over the years. The family claimed that the spirits would often appear at 5:15 a.m. to move beds and that they smelled like rotten flesh (yuck). She says that whenever her father went into the basement, he would sense a "cold, stinking presence behind him." Although they avoided the dirt-floored cellar most of the time, Roger would frequently go down there when the heating system inexplicably broke down.
The Warrens made several excursions to look at the property throughout the ten years that they were residents. Lorraine once tried to communicate with the ghosts that were possessed by the family by performing a seance. Carolyn Perron went possessed during the seance; she started speaking in tongues and got up from her chair.
Andrea asserts that she saw the seance in secret. Andrea remarked, "I thought I was going to pass out." "My mother spoke in a voice that was not her own, in a language that was not of this world. She was propelled across the room when her chair lost its weight.
Even though Ed performs an exorcism at the end of the movie version of events instead of a seance, Lorraine is adamant that she and her husband would never try one because they need to be done by Catholic priests.
Roger ejected the Warrens following the seance because he was concerned about his wife's mental health. Because of their financial difficulties, Andrea claims that the family stayed in the house until 1980, when they were able to move out and the hauntings stopped. At that time, the ghosts were said to have been placated.
Carolyn is completely taken over by Bathsheba when she shows up one morning. Cindy shows the group a secret passageway in the closet after she is drawn in by a spirit that they hear that night. When Lorraine goes down the tunnel and descends to the cellar, she witnesses the ghost of a lady who Bathsheba once possessed and used to murder her child. The attack by Bathsheba on Nancy is captured on camera. The Warrens determine that there is enough proof to obtain a Catholic Church order for an exorcism; however, Father Gordon clarifies that since the Perron family is not a Catholic, the Vatican would need to provide permission directly.
Judy, the daughter of the Warrens, is attacked by Bathsheba in the Warren residence. In order to kill Christine and April, Carolyn brings them back to the Perron family's motel. Ed, Lorraine, and Brad discover Carolyn attempting to knife Christine in the cellar. Lorraine threatens to kill Carolyn if they bring her outside the house. Ed tries performing the exorcism on himself while they bind Carolyn to a chair. Even though Carolyn manages to get away and makes an effort to murder April, Ed is able to finish the exorcism, lift Bathsheba's curse, and send April back to Hell because Lorraine is able to call to her by reminding her of a precious experience she shared with her family.
When Ed gets back to his house, he adds the haunting music box from the Perron residence to the room full of occult items they had gathered from previous instances. The music box begins to play on its own as he walks away.
Similar experiences were had by another family in Enfield, England, six years after the Perron family was terrorised by their demon. The Hodgson family first noticed unexplained sights and sounds in August 1977. When Janet, the second-oldest of the four children, plays with a ouija board, the Hodgson family in the London borough of Enfield starts to witness unusual happenings. Janet begins to sleepwalk and has conversations in her dreams with an angry old guy who sits in the family armchair and claims the house belongs to him.
The Hodgson brothers and their mother Peggy eventually experience paranormal activity, which terrifies them to the point where they flee to their neighbours. Janet becomes possessed by Bill Wilkins, an old man who had resided in the house and passed away, when the media tries to speak with the family. The Warrens are finally informed about Janet's increasing demonic possession, and they are asked for help in determining whether or not Janet's possession is a fake. Lorraine tells him not to get involved because she is afraid that her vision of Ed's death might come true. In Ed's study, she sees the evil nun once more. In a trance, Lorraine scratches the name of the demon into her Bible.
While residing at the Hodgson home, Ed and Lorraine confer with Anita Gregory and Maurice Grosse, among other paranormal investigators, over the case's validity. Gregory refutes the haunting by showing video proof of Janet intentionally ruining the kitchen. Ed and Lorraine decide to leave because they think the family is lying to gain notoriety, based on this. But when they investigate, they find that the real demon—the strong nun—is using Wilkins' ghost as a pawn to subdue Janet. Lorraine discovers that the nun had disabled her powers, keeping her from understanding the reality of Janet's possession.
When Ed and Lorraine swiftly return to the Hodgson home, they discover Janet in a state of possession and the other Hodgsons imprisoned outside. When Ed enters the house by himself, he discovers Janet at the window, prepared to end her life. He almost trips and falls, but he catches Janet in time. The yard tree is struck by lightning, transforming it into the stump that ensnared Ed in Lorraine's vision. Lorraine discovers her Bible, where she penned the name of the demon, Valak. By addressing the demon by name, she gains control over it and effectively returns it to Hell. After releasing Janet from its hold, Lorraine helps drag Ed and Janet to safety.
Once back at home, Ed puts the ghostly "Crooked Man" zoetrope toy that belonged to Peggy's youngest kid next to April Perron's music box and the Annabelle doll to add it to his and Lorraine's collection.