2000 years since their last attempt, the Underground Empire Bugnarak returns intending to conquer the whole world. To fight the invasion, the kings of the five great nations, Shugoddam, Nkosopa, Ishabana, Gokkan, and Toufu gather at Shugoddam's capital to establish an alliance, but the king of Shugoddam, Racules Hastie, has other plans. Confronting Racles for his transgressions, Gira, an orphan, steals his sacred sword and uses it to lead the Shugods in repealing the invaders.

After defending N'Kosopa from Bugnarak's attack, Gira and Yanma are kidnapped by the queen of Ishabana, Himeno Ran, who keeps a secret from them.