Twelve-year-old Curt lived in New Castle, California for all his life and thought he knew everything about the town, but he wasn't familiar with the oldest part, a neighborhood built when the Shasta Dam was constructed. Now he comes to know it up close and on a personal level when he, his mother and baby brother move into the largest house in the old neighborhood. Creepy gargoyle statues outside the front door and two evergreen trees with roots growing out of the ground, clutching their bases, hold Curt's attention. While not impressed with the neighborhood, he's thrilled to have his own room again following his parents' divorce. However, Curt's interest in his room dwindles as his bed begins to shake, in the absence of any earthquake, and seemingly endless piano music plays throughout the long nights. One night when something from under the bed grabs his leg, Curt knows he needs to get help. His mom attributes his experiences to nightmares and sleepwalking. His classmates have heard the stories of kids disappearing in the night. Curt and his peers form the Monster Busters Club and act fast to protect themselves from the monsters they call "the make believe."