1199 - 10 years after the death of Minamoto no Yoshitsune at Hiraizumi. Japan is now under the shogun Minamoto no Yoriie, son of Yoritomo, who had schemed against Yoshitsune. Yoriie hears of followers of Yoshitsune still lurk about, and is more than willing to get rid of those thorns in his side. However, they are more pertinent than he could imagine...for Yoshitsune's orphaned son, Hoshiwakamaru, has survived, and is planning to avenge his father with fellow pirates and conspiring officials! A tale of alternate history set at the dawn of the Kamakura period, with some fantastical elements mixed in.