Three boys, Takuya, Kazuki, and Dai, are sixth graders from Ishinowa Elementary School. They are a strong, curious, and mischievous trio. One day, they obtain a mysterious jewel known as the "Power Stone," which awakens Dran, a golden robot and brave warrior who had been sleeping within it. The boys become his masters. However, Prince Walter of the Walzac Empire, who covets the Power Stone, soon attacks them. Together with Goldran, the boys embark on an adventure to search for the eight Power Stones scattered around the world, all while seeking the legendary El Dorado.
