Teenager Jackie Ashmore is struggling with the passing of her mother and angry over a cross-country move to Minnesota when she receives an unexpected birthday present that opens up a remarkable fantasy world where creatures from the past and the present coexist. Aided by unlikely animal allies and an aging guardian named Nimbus, Jackie embarks on a desperate rescue mission to save her little brother Dustin who has been kidnapped by a hooded rider and stolen across the clouds. Forced to grow up, Jackie must overcome her own fears and navigate a strange land as she journeys towards a confrontation with a mysterious power named Samuel Flood, who is using the boy for his own hidden purposes. With time running out and unbearable losses mounting, Jackie faces ever tougher choices that will determine not only the fate of her brother, but possibly the Earth below as well.