One day as Reiji, Maiko, and Daisuke are training in the special training room, a strange dragon appears in the sky. Somehow this creature sucks them into the other Earth known as Rikyu. They are met by Megaru, a girl who was also transported to Rikyu, and taken to a village. There, the elder of the village explains that RI-ON, the group behind Dragon Drive, is trying to obtain the Braveheart, also known as the Jinryusenki, by training kids on Earth as their soldiers with the Dragon Drive program. If they succeed, both Rikyu and Earth will be destroyed. This is where Chibi (Chibisuke in the Japanese version) and Reiji come in. Chibi is actually the legendary dragon Senkoukura, the savior of Rikyu. To protect the Braveheart, Reiji and company must enter the Dragonic Heaven tournament and win. Unfortunately RI-ON has already sent someone to enter the tournament as well.
Reiji is torn between what side to fight for as he does not believe that the employees of RI-ON (or, more accurately, Agent L, a woman who helps Reiji through his first few Dragon Drive games) are bad people but at the same time, believes that Megaru is speaking the truth. In the end, he resolves to fight in order to learn the truth about RI-ON, Rikyu and Dragon Drive.