Schatzritter plot
After the mysterious death of his mother seven years ago, eleven-year-old Jeff lives alone with his father in their own campsite on the edge of the ruins of a castle belonging to his family. Jeff is apparently not all alone in this uninhabited area, and his overprotective father forbids anything that could be fun. Fortunately, it's summer vacation again and Jeff is finally back together with his gang, who come to holiday camp every year. But when the gang stumbles upon a clue about Jeff's late mother, a big and dangerous adventure begins for the kids...