This is labeled as one of the scariest movies out there so if you don’t want to know the Paranormal Activity Spoiler then I would suggest you move on. But if you do want to know the Paranormal Activity Spoilers from beginning to end, then please continue.
Paranormal Activity Summary and Spoiler
Paranormal Activity begins with Micah testing out his video camera. He wants to try to get all the paranormal activity recorded and documented that takes place in the house him and his wife just moved into.
A psychic is called in and we learn that Katie has been haunted by some spirit or demon since she was a child. The couple thinks its some ghost but the psychic informs them that it is a demon following Katie wherever she goes. So, even if they move out, the demon will follow her wherever she goes.
The psychic then goes to tell them the demon feeds off negativity and tells them they shouldn’t argue or even try to antagonize it.
Micah starts recording for the first night and sets up the camera in the bedroom. The first night, nothing happens. But slowly yet surely weird things starts happening. Small things such as the door moves or the hallway light turns on while the couple is asleep.
One day Micah decides to antagonize the demon by trying to talk to it and ask if he should get a Ouija board. Katie doesn’t want him to and wants him to stop trying to antagonize the demon. Of course, he doesn’t listen and gets one anyways.
After they get one, Micah and Katie argue about it. They go outside and Katie is yelling and while this is going on, the Ouija board spells out a word and then catches on fire.
Stranger things then start happening including Katie getting up in the middle of the night just standing along the bedside of Micah and staring at him for hours. Then she’ll leave and go downstairs. Micah would wake up the next morning and find her on the swings.
Katie doesn’t remember any of this.
After all of this, Katie let’s Micah do one more experiment. He would put powder on the bedroom floor and the next morning they would see footprints. Obviously they were footprints of something that is not human.
They try to call a demonologist but they are out of town. They try to call the psychic back and the next morning he comes, he feels the negative vibe so much that he basically just runs away and doesn’t even want to enter the house.
The nights become scarier. One night the bed sheets move and Katie is dragged out of the bed screaming. Micah wakes up and takes her back. The next morning she ends up all bruised and it looks like she was bitten.
The paranormal activity gets worse as it starts happening during the day time as well. One day Micah finds Katie sitting on the floor holding a crucifix with blood on her hands. Micah wants to leave to a hotel but Katie now refuses.
He leaves the room anger.
That same night while they’re sleeping. Katie suddenly gets up and stares at Micah for hours. Eventually she walks downstairs and she screams for Micah in which he jumps up and runs to her. There is a lot of screaming from both of them and then all of a sudden there is dead silence.
You hear loud thumping sounds coming up the stairs. Then you see Micah’s body thrown at the camera and both are knocked down. You see Katie then come over and sniff him and then smile at the camera because she is possessed.
Then she slashes at the camera and then it goes all black.
Update: A alternate ending mentioned by a commentator, Steal, says:
She comes up with the knife and sits there rocking all the rest of the night, then the next day her friend comes to find out if she and Micah are alright since they are no longer answering the phone
After coming into the house the friend sees Micah on the ground (off camera) and the police come.
Micah is pronouced dead, and they come up finding her rocking on the floor still with the knife. She gets up and comes at them with the knife and is then shot dead.