

David and Lisa are summoned to the palace of King Conrad. The king lives behind a waterfall and has a jester named Tim. King Conrad tells the gnomes he wants them to go to the island of Mentoa and find the valuable shadowless stone. The stone is a royal treasure and it is stolen by the trolls. David and Lisa jump down a deep hole, then sail across an eerie red sea. David and Lisa enter Mentoa, a mountain with 1000 steps leading to the top. At the top of the stairs is a chamber holding the stone. Once David picks it up, the trolls materialize out of thin air and chase him and Lisa down the steps. But the trolls can not exit the mountain, because only a person with a kind heart can open the entrance door!
In the first episode ""Good Medicine"" we are told some facts that Gnomes, such as their height, weight, strength and what they like to eat. David also tells us all about their enemies, the Trolls.
Lisa is very worried about David and Swift, their red fox, when they don't arrive home from a trip in ""Witch Way Out"". In fact, they have been captured by some trolls called Hooley, Pat and Poopey. Lisa goes out to search for them and when she finds them, she has to set up a resuce mission. What can she do to save them?
David is called to Italy to treat a gnome girl. She had eaten a strawberry that had been sprayed with pesticide. The only plant that can cure her is the Shining Begonia. David travels to the Alps and outsmarts a snake to find the flower. On the way back, he meets Pot, one of the trolls.Pot challenges him to a dancing contest, and David cleverly keeps Pot waiting until the sun comes up. The troll turns into stone in the sunlight. David goes back to the palace and revives the gnome girl.