Paranormal Activity 2 is a 2011 American supernatural horror film directed by Tod Williams and written by Michael R. Perry. The film is a parallel prequel to the 2007 film Paranormal Activity, beginning two months before and following up with the events depicted in the original film. It was released in theaters at midnight on October 22, 2010, in the United States, Mexico, Poland, Ireland, United Kingdom and Canada.
After experiencing what they think are a series of "break-ins", a family sets up security cameras around their home, only to realize that the events unfolding before them are more sinister than they seem.
In 2006, a "burglary" occurs at the home of Kristi (Sprague Grayden) and Dan Rey (Brian Boland). Every single room is completely trashed except for their infant son Hunter's bedroom. The only thing stolen is a necklace that Kristi's sister, Katie (Katie Featherston), had given to her. Dan installs a number of security cameras throughout the house to watch over their son, Hunter. The family starts to hear noises and see items fall or move on their own. Martine (Vivis Cortez), the family housekeeper and nanny, believes evil spirits are the cause and attempts to cleanse the house of "evil spirits," and Dan fires her after catching her burning sage. Katie and Kristi talk about being tormented by a demon or unknown spirit when they were children. Dan's daughter, Ali (Molly Ephraim), begins investigating the mysterious happenings. She discovers that on occasion, a human can make a deal with a demon for wealth or power by forfeiting the life of their first-born son. She also realizes that until Hunter, there had not been a male child born in Kristi and Katie's family since the time of their great-great grandmother.
The violence continues to escalate, and Kristi is tormented further; the family's German shepherd dog, Abby, is attacked and pulled violently off camera and apparently suffers a seizure. Dan and Ali take the dog to the vet, leaving Kristi alone with Hunter. She goes to check on the baby and notices a light flicker off. She turns the light back on but then is dragged by an unseen force out of the room and halfway down the stairs before she is released. Kristi runs back upstairs into Hunter's room but is violently dragged back downstairs. This time she is dragged into the basement where she stays for several hours. Finally, the security camera footage shows the basement door opening and a possessed Kristi walking through the living room.
The following day, Ali is at home with Kristi, who won't get out of bed. Ali looks at the inside of the door to the basement to find it covered in scratches and a single word, Meus (Latin for "mine"), illegibly scratched into the door. After hearing noises, Ali finds Kristi ignoring Hunter but aggressively demands she not touch him. Ali cries downstairs waiting for Dan to arrive home to bear witness to Kristi's strange change of character. When he arrives, Ali, who has now watched the security tapes from the night before, begs him to view the footage of Kristi's attack. Upon watching the evidence, he immediately calls Martine, who then prepares a cross that will pass the demon onto another blood relative, and that Kristi will have no memory of having been possessed. Dan tells Ali that he is going to pass the demon onto Katie so that Kristi and Hunter will be saved. Although Ali pleas with him, begging him not to because it is not fair to Katie, Dan sees no other way to save his wife and son.
That night, when Dan tries to use the cross on Kristi, she violently attacks him, and all the lights in the house go out. They turn the night vision of the hand held camera on, and find that Kristi has disappeared after snatching Hunter. Furniture all over the house begins toppling over, and the chandeliers in the dining area shake. Dan chases Kristi into the basement and after a few minutes of looking for her, she attacks him. He touches her with the cross, causing her to collapse to the floor, the camera facing the other way as the ground rumbles. Inhuman growls and roars are heard, until it finally stops suddenly. The next scene shows Dan putting Kristi to bed and then burning a photo of a young Katie, which Micah (Micah Sloat), Katie's boyfriend, would later find in the attic of their house.
Three weeks later, on September 18th, Katie visits and explains how things have now begun happening at her house. After Katie leaves, she is shown at her and Micah's house, where he has just purchased a new video camera (the scene shows approximately the first 2 minutes from the first film). On 9th October - the night after Micah is murdered (in Paranormal Activity) - Katie, possessed and bloodstained, breaks into their home and kills Dan by breaking his neck. She then climbs the stairs and confronts Kristi in Hunter's room, violently hurling her against the wall and taking the baby. The final scene is Katie leaving the room, cradling Hunter with a satisfied look on her face.
An epilogue text states that Ali was on a school trip and returned home on October 12th to find her father and stepmother dead and that Katie's and Hunter's whereabouts remain unknown.