The Ending Of Paranormal Activity Explained

After the attack, Katie begins to act very strangely. Micah is clearly overwhelmed by the sudden escalation and focuses on packing their things to temporarily move to a hotel. During the process, Micah finds Katie in a catatonic state, clutching a cross in her hands. She's unresponsive, and she's grasped the cross so hard that her hand is bleeding. Micah, seemingly at his wit's end, throws the cross into the fireplace and moves Katie upstairs while he continues packing. 

Once Micah has everything in order, he heads upstairs to retrieve Katie. To his surprise, Katie has had a complete change of heart about leaving the house and begs him to stay in the home with her, insisting they'll be safe there after all. Micah gives in to her request, unaware that the Katie he knew is gone for good. The next night, the camera feed shows Katie exiting the bed while Micah is still asleep. For two hours, Katie silently watches Micah sleeping before heading downstairs. Suddenly, Katie releases a bloodcurdling scream, and Micah springs into action. 

Falling victim to the demon's trap, Micah leaves the room, and the camera continues rolling as the action happens offscreen. After a few moments of Micah screaming, silence follows. Then Micah's body is suddenly thrown at the camera, knocking it down. The obviously possessed Katie crawls into the frame with a menacing grin, and just before the film cuts to black, her face changes into a demonic-like figure as she lunges, screaming at the camera.