|Portrayed by||Kathryn Newton|
|Year of Birth||1996|
|Age||15 (as of PA4)|
|Appearance(s)||Paranormal Activity 4|
|Last Seen||November 17, 2011|
|Relationships|| Holly Nelson (Mother) (Deceased),|
Doug Nelson (Father) (Deceased),
Wyatt Nelson (Adopted Brother) (Missing, Assumed Alive),
Ben (Boyfriend) (Deceased)
Alex Nelson is a fifteen year old high school student (9th/10th grade). She is the main protagonist of Paranormal Activity 4. Like other protagonists, Alex is the only one who suspects anything is going on throughout most of the film. She is reserved, smart, well-behaved, and resourceful in precarious situations.
We meet Alex as she is filming her little brother, Wyatt as he is playing soccer. While filming, she catches Robbie on the camera standing still and silent at the other side of the field. Then her, Wyatt and their mom, Holly, all sit down for lunch but have to wait for their father, Doug. While Holly and Doug have a fight Alex tries to teach Wyatt how to do a cartwheel so as to distract him.
At home we meet her friend Ben and they hang out while her parents are gone. Afterward she shows Ben the playhouse and they both go into it. As Ben goes in he is startled to see Robbie standing there in the corner. Alex is unfazed by this and merely brings Robbie back to the house.
Later that night there are cop cars outside Robbie's house and Robbie's mom has to go to the hospital. So, Holly takes in Robbie saying, "He has nowhere to go."
Robbie and Wyatt become instant friends and are often playing. At one point Holly goes in with Ben into the playhouse and Wyatt talks about Robbie's imaginary friend. Alex asks Robbie what his name is and Robbie calls him. Alex, trying to play along, says that she can see him, but Robbie tells her that she's faking it and she can't really see Toby.
Later that day Wyatt is playing two player on the Kinect and Robbie is sitting on the couch. Alex and Ben walk in and ask who Wyatt is playing with and Robbie says it's his imaginary friend. And then the Avatar that Toby would be playing begins to move. Then, Ben asks if they want to see something cool and he turns on the tracking dots on the Kinect and they all start dancing. Later when Alex and Ben are reviewing the footage they see a figure moving next to Robbie.
The next day Ben tells Alex that webcam chats are automatically recorded and he saw Robbie going into her room and sleeping next to her. Alex asks Ben if he can do this with any computer, he says yes, and so together they turn every computer in the house into a camera.
Over the next couple of days the cameras record strange things. All of which Alex is privy too. At one point when she's home with Wyatt and Robbie, she walks into the room to find Robbie painting a bunch of symbols on Wyatt including an eye-type symbol (first appeared in Paranormal Activity 3) that she later finds to be part of Hittite rituals.
On another night Alex notices several black cars outside Robbie's house while she is chatting with Ben online. She goes outside to investigate and sees several women all dressed in black. One woman walks up to Alex and startles her, causing her to run away.
And the next day while Alex is alone she hears strange noises and she steps out of her room and sees a trail of toys leading to a little crawlspace, similar to the one in Paranormal Activity 3. She opens it and feels Toby run past her, a toy train turns on, which she turns off, and downstairs a chandelier is swinging by itself. She takes a step towards it when a chandelier in the room she is in crashes to the floor, almost killing her. She sees Robbie right above her and demands to know what is going on but he is silent. When Holly and Doug come home they think it's just a faulty installation but Alex insists that it is something else.
The next day, Alex notices Wyatt and Robbie going to Robbie's house. Alex follows them and enters the house. She thinks she hears screaming but really it's just Wyatt and Robbie tickling each other. Then she is startled when she sees Robbie's mom, Katie. Alex quickly leaves with Wyatt in hand.
After this Alex talks with her mom about what had happened. Holly then says that Katie called and but she missed it, but Alex retorts, "How would Robbie know that?" Holly simply dismisses this.
Later, Alex talks to Wyatt about why they went over to Robbie's house without telling her. Wyatt says Robbie had said it was time and Katie said Wyatt was adopted just like Robbie. He also says his real name is Hunter, despite Alex's contradictions.
The next day, Alex is home alone talking with Ben on the computer when suddenly the garage door opens. She goes to the garage and closes the door and goes back to the kitchen when the garage door opens again. She goes back to the garage and suddenly the garage door slams shut and so does the other door and the car turns on with the engine revving violently, filling the garage with carbon monoxide. Alex picks up a golf club, smashes a window of the car, gets in, and crashes it through the garage door, giving herself fresh air. When her parents return home, they aren't convinced by her story.
That night, Wyatt walks into Alex's room and levitates her above the bed. Having taken sleeping meds to calm her, Alex is not awakened.
The next evening Alex and Doug go out for dinner but as they are driving back to the house, they see Katie and Wyatt going together to Robbie's house. Doug goes and investigates while Alex goes upstairs to her room where she finds Ben's body in her closet. An unseen force pushes her onto her bed and drags her out of the room, but she manages to escape and runs to Robbie's house to get her dad. She enters the house and sees her dad for a moment before he is dragged out of sight by Toby. She comes to a room with windows lined with newspapers written in Spanish. As she tries to leave she encounters Katie. Her face contorted in a demonic scream, Katie charges Alex, who retreats to the room and slams the door. As Katie claws her way through it, Alex escapes out the window into the backyard and sees Wyatt standing there. She desperately tries to get Wyatt to come with her but Wyatt is staring blankly past her. Alex turns and sees a group of cult members, slowly advancing towards her. She turns around only to end being attacked by a possessed Katie. The camera then goes dead.