Sadie's class camps in the woods. To pass time, they tell ghost stories. After hearing the story "Legend of the Mysterious Cave" Val, Sam, and Doug decide to explore a cave.. that's actually a portal to the magical realm!

When Gilbert and Sadie get into a squabble in front of the Wardens, they're sent packing with a transformation spell as homework. To make things worse, the Wardens decide to send a magical cat as mentor to Sadie's home.