One moonlight night Amber sees a strange creature called Sunflower through her bedroom window. Sunflower invites her to visit its friends called Moonies, that live in caves. The friendly creature persuades her to watch the Moonies dancing.
Soon afterwards a fearsome monster flies overhead and the terrified Moonies take shelter in their homes, followed by Amber and Sunflower who are chased through a forest by the Wortoron, a terrifying enemy of the Moonies. They discover that one of their friends called Fuzzy has been carried off by the monster. Amber and some of the Moonies which can fly set off to rescue their friend.
Amber rides on the back of a winged creature called Horse and they follow the Wortoron to its mountain lair. Amber and her brave helpers have many scary adventures in underground caves, lakes, and dark forests, and eventually win a battle with the monsters high in the sky.