Tibben is the potions apprentice, and helps Grandpa make spells to sell in their shop. Along with Wizz, a magical creature with a special gift for finding things, they set off on adventures to help the animals of Arthwen. When the Water Sprites of Lake Sapphire start to feel poorly, it's up to Tibben and Wizz to find out what's making the magic waters of the kingdom dirty - can they solve the mystery?