Isanami, a teenage priestess of Izumo, is forced to witness as a gang of wicked ninja burn down her temple and massacre the people within, giving her no choice but to flee into the wilderness to avoid the same fate. She meets Saizou Kirigakure, a masterless ninja from the Iga school, by happenstance. They proceed to Ueda Castle to seek assistance from Yukimura Sanada. Isanami's odd and destructive power is revealed, and Sanada gladly offers to assist her, rallying 10 courageous warriors to her side. This is how Brave 10, a narrative set during the Warring States period, begins. It follows Saizou and Isanami as they travel across war-torn nations in quest of courageous soldiers to serve under Yukimura's banner.