Paranormal Activity 2 (2010)

In August 2006, a "burglary" occurs at the home of Kristi and Daniel Rey, trashing their house and leaving only their infant son Hunter's bedroom untouched. The only thing stolen is a necklace that Kristi's sister, Katie, gave to her. Despite this, the family contact a home security company and have them install security cameras around the house. Martine, the Latin American family housekeeper and nanny, senses "evil spirits" in the house and burns sage to rid the house of them, and Daniel fires her for doing so. Kristi also believes that their home is haunted, and she and Katie talk about being tormented by a demon when they were children. Daniel, however, initially dismisses her claim despite footage of strange occurrences around the house. Daniel's daughter from a prior marriage, Ali, begins investigating the mysterious happenings; she discovers that humans can make deals with demons for wealth or power by forfeiting the soul of their first-born son, but if the deal is not fulfilled, the demon will stick to the family until another son is born — Hunter was the first male to be born on Kristi's side since the 1930s.

The violence escalates, as the family's German Shepherd, Abby, is attacked by the demon and apparently suffers from a seizure. As Daniel and Ali take Abby to the veterinarian, Kristi is attacked and dragged into the basement by the demon, who possesses her. The following day, Ali is left home with Kristi, unaware she is possessed. Soon, Ali hears a scratching sound from the basement door and opens it to find scratches and sees a word, meus (Latin for "Mine"), etched into it. A strange bite mark on her leg and the footage of Kristi's attack motivates Daniel to contact Martine for assistance, and she prepares a cross to exorcise the demon; Kristi will have no memory of having been possessed. Daniel plans to pass the demon onto Katie so that Kristi and Hunter will be saved, despite Ali's protests.

That night, when Daniel tries to use the cross on Kristi, she attacks him and the house lights all go out. Using the handheld camera's night vision, he walks around the shaking house into the basement, where he is attacked by Kristi; he retaliates against her with the cross, causing her to collapse and the house to shake violently before settling down. Daniel puts Kristi to bed and with Martine, burns a photo of a young Katie, passing the demon onto her.

Three weeks later, Katie visits and explains that strange things have begun happening at her house. On October 9, the night after Micah is killed, a possessed and bloodstained Katie breaks into the Rey house, kills Daniel and Kristi and then takes Hunter with her. A title card explains that Ali comes home from a school trip to find their bodies, and Katie and Hunter have vanished.