In the 16th Century, a Dutch ship sails the Pacific from the Americas in order to escape the Spanish. Blackthorn is the pilot of the ship and the first to realize the possibilities of Japan. Japan is a feudal society which has a strong presence of the Portugese. A struggle is in the final stages for who will be the Shogun, the leader who, under the emperor, governs the land. Toranaga sees in Blackthorn things he can use to at least survive the struggle to come, and if both play their hands correctly, become Shogun.