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.

After a storm, another rift has opened between the human world and the magical realm. The Wardens get Sadie to help seal it, but she insists on bringing her school project, a watermelon "baby", along for the ride.

In the cafeteria one day, Sam stumbles with his tray of food. On a reflex action, Sadie shoots out a spell to stop him falling, which results in Sam and his tray levitating in front of everyone. Will her magic be exposed?