Part One: The Switch
Nicole has the worst life ever. Her parents care about her so much that they ask her to call when she's going to be late and make her stick to a curfew. One of her teachers told her that she won't graduate if she doesn't turn in a paper that she didn't even bother doing. Even though it was due that week, he lets her have an entire weekend to work on it. What a drag. Oh and her boyfriend doesn't know what she's thinking so he breaks up with her. Poor girl.
At the end of the school day, she runs into her best friend Lucy. Lucy has a super cute boyfriend named Kent but her parents fight all the time and don't have time for her. Lucy comes up with a great idea: they'll switch bodies. She takes her deep into Fear Street Woods and shows her the Changing Wall that her grandfather told her about. They climb on top, hold hands, and jump over the side. When they open their eyes, they really are in different bodies.
Nicole heads to Lucy's house, only to find the bodies of her friend's parents laying dead on the ground. She rushes to her own house, but Lucy and her parents are gone. She then heads to Kent's house. Kent tries to calm her down and refers to her as Nicole instead of Lucy. When he goes to get her water, she hears him on the phone with the cops and agreeing to keep her busy until they get there. Worried, she runs back to Lucy's house and discovers that all of her clothing is missing and that there's a bloody knife on her desk.
Part Two: The Murder
While holding the big ass knife, she finds a note that Lucy left admitting that she killed her parents. That causes her to run out of the house, but then she sees two cops outside. They get in the house and come after her, but she rushes outside and manages to get through a fake spot in the fence that Lucy's dad put in for them when they were kids.
Nicole goes back to Kent's house thinking that Lucy might be there. Instead of finding her friend, she finds Kent decapitated with his body on the floor and his head on the couch. Since she still has access to her car, she runs back to school, grabs the car, and takes off. While driving around town, she sees Lucy in a car with their friends Margie and Hannah. By the time she parks her car and runs over, Lucy is gone. The other girls say she wasn't there, but she thinks she was. She runs all over the place and thinks she sees her in a store and then by her car. Margie grabs her, but she pushes her down, gets in the car, and races off.
Thinking that she just needs to switch back, she takes a picture of Lucy to the wall and jumps over the side. Of course nothing happens, so she goes back to her own house. After changing clothes and grabbing the only cash she has on hand, she goes to Shadyside High and hangs out in the locker room. Nicole convinces herself that Margie and Hannah know the truth about Lucy.
Margie hurts herself in gym class, and since she's alone in the locker room, Nicole pops out of a storage closet. She starts blathering about the Changing Wall and Lucy, while Margie pretty much just stares at her in shock. Margie finally admits that she does know where Lucy is and agrees to go to the wall if Nicole will come back afterward and wait for her parents. They hear someone coming in, so she jumps back in the closet. She comes out to find Margie's dead body on the floor. Assuming it was Lucy again, Nicole decides to go see Lucy's Grandma Carla who is the one person they both love and trust.
Part Three: The Reunion
Grandma Carla looks happy to see her, up until the point where she demands to know where Lucy is hiding. The older lady promises to get her food, but she then hears her on the phone with the police. Nicole takes off running outside and eventually finds Lucy. The only problem is that she says Lucy made her switch bodies with her earlier that day and that she's really Nancy.
After the other girl cries, Nicole believes her, but then she laughs and says she's actually Lucy. They fight, Lucy takes off, and Nicole runs after her. She sees Lucy fall over the side of the well, but then someone grabs her from behind. It's Kent! He tells her that he's fine and obviously not dead, and when she tells him about Lucy, he tells her to let Lucy drown in the well. She rushes over to the well and grabs her hand, but then she feels her hand slipping out and hears a loud splash at the bottom.
Lucy pops back up, grabs Kent, and tries to rip his head off. Nicole screams and closes her eyes. When she opens her eyes again, she sees her parents, Kent, Grandma Carla, and the two people she thought were cops who were actually hospital workers. We find out that Lucy died in a car accident and now Nicole has crazy hallucinations where she sees people dying in front of her. They thought it was over but she had another break down. The workers are there to take her back to the hospital.
The last chapter deals with Nicole being at the hospital and how well her recovery is going. She thinks it's pretty cool that she's getting better and that the doctors helped her so much, but she also thinks it's pretty cool that Lucy comes to see her every day...