The film opens with a scene left off from Paranormal Activity 3 where Katie and Kristi are watching Dennis getting his spine crushed by a mysterious force. Grandma Lois takes the girls upstairs while an unseen force takes the camera with them. They all go into a dark room while a man encounters the girls and talks to them about "Toby" and how they are critically important to his plan.
After a young woman (Olivia Taylor Dudley) begins to express increasingly erratic and strange behaviors, her father (Dougray Scott) and boyfriend (John Patrick Amedori), along with a priest (Michael Peña) and two Vatican exorcists (Djimon Hounsou and Peter Andersson), come to realize that she's been taken over by an ancient satanic force.
A violent slaughter occurs in an abandoned house in Louisiana where three college students are found dead. Detective Mark Lewis (Frank Grillo) examines the crime scene and finds a shocked survivor, John (Dustin Milligan) before calling reinforcements. Several police cars then arrive at the house alongside an ambulance and a psychologist, Dr. Elizabeth Klein (Maria Bello). She talks to John, who tells her that a seance performed in the house called the attention of many spirits, including one he identified as his mother, and that two of the group members, consisting of his pregnant girlfriend and her ex boyfriend, are still missing.
After his mother is institutionalized, misfit Brodie is sent to live with his fundamentalist Christian Uncle Albert and Aunt Mary, whose son David torments him. A heavy metal fan, Brodie forms a band called Deathgasm with his friends Zakk, Dion, and Giles. When the bandmates break into a local house, they discover that one of their idols, reclusive musician Rikki Daggers, lives there. Daggers gives the band magical sheet music, which a cult later murders him to find. Skeptical of the sheet music's power, the band plays it, only to summon a demon. With the help of his crush, Medina, and his bandmates, Brodie must find a way to defeat the demon.
On June 6, six women in a close-knit Amish community go into labor and deliver six girls, sparking fears that they could fulfill an ancient prophecy. The prophecy states that six girls will be born on the sixth day of the six month (6-6-6) and that one of them will become the "Devil’s Hand". Out of fear, one mother kills both herself and her daughter shortly after her birth, and the remaining five girls grow up with relative ignorance of the prophecy. As they come closer to their eighteenth birthday, their actions are constantly monitored by the community, especially Elder Beacon (Colm Meaney), who views any ungodly actions as proof that one of them is Satan's minion. This is all made more troubling by the fact that one of the girls, Mary (Alycia Debnam-Carey), has started having terrifying visions that could suggest that she is the Devil's Hand. As tensions rise, a mysterious figure begins to murder the girls one by one.
In June 2012, high school graduate Jesse Arista lives with his father, sister and grandmother in Oxnard, California. He begins to enjoy the summer with his best friend, Hector. In the apartment below lives a mysterious woman named Ana, who everyone believes to be a witch. When Ana is found murdered, Jesse and Hector spot classmate Oscar running from the scene, suggesting he was responsible. The two investigate the apartment, where they find black magic items, as well as VHS tapes and a journal of spells that can "open doorways to 'unholy lands.'"
The film starts with the same opening scene from The Conjuring, in which two young women and a young man are telling Ed and Lorraine Warren about their experiences with a doll called Annabelle which, they believe, is haunted.
A teenage girl (Ashley Rickards) is told by her new boyfriend that she can get $500 by playing a game run by an old man living in a trailer. After she wins the game, the old man (Michael Massee) instructs her to go to the crossroads and say her name so that "he" will know who to take. At home later that night, the girl hears voices before being lifted into the air.
The film opens with the GEOs sent in to recover Ángela. They begin setting bombs all over the apartments, but when they're ambushed by the infected Manu and the old man, they then kill them off and kill the officers infected as well. They then hear Ángela's screams for help and tell her it is time to get out.
The film opens in a 2010 firefight in a palm grove in the Diyala Province of Iraq. Three Marines discover an underground cavern and start to scream as their helmet video feed goes black. In The Bronx in 2013, NYPD officer Ralph Sarchie (Eric Bana) stands over the corpse of an infant in a darkened alley. He and his partner Butler (Joel McHale) resume their nocturnal patrol for the 46th Precinct. A domestic disturbance call comes in over the radio. Sarchie probes the dispatcher for more information and finds out that the male at the address is a former Marine. He tells Butler that his "radar" is going off because maybe the former Marine still thinks he is fighting in the war.
After his beloved wife Samantha (Cara Pifko) dies after receiving poor advice from a psychic, atheist Michael (Shane Johnson) decides to focus on the supernatural for his next film as a way to disprove the existence of God and the Devil. He chooses to achieve this by visiting various people and having them perform various spells and rituals on him. He begins with Beverly (Dale Dickey), the psychic who was partially at fault for Samantha's death. From here he ends up in various different scenarios, all of which involve the supernatural. However even as Michael does this in the hopes of reaffirming his own atheism, he becomes the focus of several dark, supernatural forces that are intent on exerting their influence on him.
Carson Morris (Lara Vosburgh) is a former straight-A student that has been using drugs for the past year, having begun shortly after she enrolled in a prestigious Catholic high school. She has agreed, albeit reluctantly, to allow a film crew to monitor her for an Intervention-esque documentary show as she checks into a rehab clinic. Carson is quickly made a target of ridicule by the other patients, as she has been taking drugs because she believes that she has been demonically possessed. Jason (Morgan McClellan), a production assistant for the film crew, is sympathetic and quickly bonds with Carson - even going so far as to believe her claims after her behavior turns increasingly erratic. During all of this Carson also has several displays of supernatural behavior that is captured on camera but only when she is alone. There are suggestions of bringing in an exorcist, however the clinic's physician Dean Pretiss (Richard Wilkinson) thinks that this would be detrimental to Carson's mental well being. When Carson attacks Jason the show's producer Suzanne (Kate Whitney) begins to push Pretiss for an exorcist, only for him to state that he wants to transfer Carson to a mental institution.
Jay Baruchel arrives in Los Angeles to visit with old friend and fellow actor Seth Rogen, who invites him to attend a housewarming party hosted by James Franco. Jay is uncomfortable being around so many people he hardly knows, so Seth accompanies him to a convenience store for cigarettes.
A couple, Jared (Judd Lormand) and Lily (Boyana Balta), finds a demonic-looking Nell Sweetzer (Ashley Bell) squatting next to their refrigerator. She soon is taken to a hospital, where she appears to be catatonic. After spending a few months at Frank's (Muse Watson) home for girls in New Orleans and settling in as a chambermaid at a hotel under the supervision of her boss Beverly (Diva Tyler), Nell's condition seems to have improved and she no longer has "bad dreams". Nell and her group of friends Gwen (Julia Garner), Daphne (Erica Michelle), and Monique (Sharice Angelle Williams) attend a Mardi Gras parade; Nell witnesses many strange happenings there, including masked men watching her. Her personality changes as things get darker. She begins to get hints that the demon Abalam is back.