Furious that her late father only willed her his gloomy-looking mansion in lieu of his millions, Carrigan Crittenden is able to melt away the location for the ground when she discovers a map to a treasure hidden within the house. But when she enters the rickety mansion to search for her declare, she is frightened away by a wicked wave of ghosts. Decided to acquire her palms on this hidden fortune, she hires afterlife therapist Dr. James Harvey to exorcise the ghosts from the mansion. Harvey and his daughter Kat transfer in, and quickly Kat meets Casper, the ghost of a young boy who's "the friendliest ghost you recognize." But not so pleasant are Casper's uncles--Stretch, Fatso and Stinkie--who are determined to drive all "fleshies" away. In the end, it can be up to Harvey and Kat to help the ghosts cross around for the other facet.