This time, Davidia and Slirander's adventures take them to the old clay-quarrying town of Humpletoon to look for Davidia's long-lost, distant relative, Aunt Mavis. The quarry is made up of a special seam of clay used by the town's potters to turn out specialist mug off erings which they use to compete in the Dimpletoon Mug Festival. Scrool fiercely guards the Ring of Clay, using its ancient secret of using red ruby eyes to protect its inhabitants from greedy humans whose actions will cause extinction of this lost race. The town also holds another secret - the true ownership of the land. The only thing holding back the town from bulldozing the quarry is the council's inability to purchase the dilapidated house standing on the quarry edge in which lives an old "witch" who is unwilling to sell. The townsfolk believe she is cursed and are therefore scared to make contact with her. This is Aunt Mavis' way of keeping people away - camouflaging her real younger identity behind the dirty, flowing rags and a modern home underneath the pretend, dilapidated structure, the eyesore of the town. To help Aunt Mavis claim her rightful ownership of the quarry and save it from destruction, the girls get involved in her plan, engaging in secret activities including a role-play, talking with Milo Mac, interpreting secret messages from Scrool, the keeper of the Scroll of Scrollinger, and confronting the town's antagonists to retrieve stolen items which reveal Aunt Mavis' true identity as owner of the land. Another fascinating adventure in the Davidia series as these best friends once again stake their claim on being able to solve a mystery during their school holidays.