Holger Nilsson is forced on a raging treasure hunt to find the seven keys to his world-famous relative Mary Diana Graaf's mythical laboratory. To help him, he has the inventor Mortensen and Mary Diana's GPS computer with pre-recorded riddles and clues written in verse. But what kind of mysterious and malevolent figure lurks in the background?

Ce synopsis est en anglais : nous ne l'avons pas encore traduit.