Erin Dodgeson loves her new home. It has a big backyard with a treehouse, and she doesn't have to share a room with her annoying little sister, Becca. Everything is perfect...except for the ghost. At first, the ghost is just a nuisance. But then Erin starts losing her memory, sometimes it's only for a few minutes; other times, it's for a few days. Erin is convinced the ghost has been taking over her body, but doesn't know exactly know why or how or how to make it stop. All she knows for sure is she'd better do something before the ghost takes everything from her.