During Japan's feudal era, there was a war between two ninja clans: the Byakuro and the Kabusu. One night, the Kabusu staged a fierce attack on the Byakuro castle in hopes of kidnapping the clan's infant princess. Their mission was foiled when a loyal ninja of the Byakuro flees the attack with the princess and disappears, eventually raising her to be a ninja. Several years later, six ninja trainees are given a missio...