Fourteen-year-old Oscar Peregrin has a lot on his plate. With the help of a tiny green dragon, Hercules, and a blue-haired girl, named Anthia, he embarks on the most dangerous mission ever, across Etherea, to discover a magical stone, named Sphragidus, the only one that can eliminate Shadow, leader of the Underworld. The plot thickens when Oscar falls in love and comes upon the most tremendous secret of the Underworld, the Silent Magician.