Peter and Martin wuld rather live on top of Popcorn Hill than anywhere else in the world. There is always someplace exciting to explore with their new dog Rosie. But things turn scary after a weird laughing ghost appears in their bedroom at night. It seems he is lonesome and wants to be friends. As the boys try to get rid of this creepy night-time visitor, they discover there is more than one ghost on Popcorn Hill!