Japan's warrior class rules for more than seven centuries, and this film traces that arc from the Heian Period through the mid-1800s, when the country's forced opening in 1853 ends their dominance. Scholars and modern martial arts practitioners walk through the samurai's training, weapons, and the Bushido code that bound them to duty and honor. The film narrows its focus to one life as a case study: Tokugawa Ieyasu, born in 1543 the same year Portuguese merchants become the first Europeans to land in Japan, spends part of his childhood as a hostage before rebuilding his family's domain and allying with Oda Nobunaga and Toyotomi Hideyoshi. His army's victory at Sekigahara earns him the title of shogun, and in 1614 he turns on Hideyoshi's heir, attacking Osaka Castle in a assault that kills more than 100,000 and opens two and a half centuries of Tokugawa rule. Ceremony and battlefield sit side by side throughout, tracking how samurai power actually changed hands.