12th century, Japan. Charismatic leader Minamoto no Yoritomo founds the Kamakura Shogunate, shifting the political powerbase from Kyoto to the east. Behind this military feat are thirteen vassals. But after the superstar shogun's death, a fierce power struggle erupts. The one out of the Thirteen who emerges on top is Hojo Yoshitoki, the youngest of them all. How did this young samurai, who started with no such ambitions, become the greatest warrior in the country? It's a ruthless game of intrigue in the new capital Kamakura -- Yoshitoki must play his cards carefully.