In medieval Japan, eight-year-old Hojo Tokiyuki is the heir to the Kamakura shogunate. But the Hojo clan is in decline, and Tokiyuki's peaceful days of playing hide-and-seek with his teachers come to an abrupt end when his clan is betrayed from within. The lone survivor of his family, Tokiyuki is the rightful heir to the throne, but to take it back, he'll have to do what he does best--run away!

After years of training and deadly battles, the combined Hojo and Suwa army, with Tokiyuki at its head, has defeated Ashikaga Takauji's forces and retaken the city of Kamakura! Tokiyuki and his retainers celebrate their return, then they seek the services of the legendary swordsmith Masamune, asking him to forge personalized weapons. Meanwhile, Emperor Go-Daigo, shocked and confused by the defeat, orders Takauji himself to ride forth at the head of his army to attack and destroy Tokiyuki once and for all!