The novel is set in a time extending from the late 15th through the 16th century in Japan, when a weak central government was largely relegated to the sidelines while numerous warlords vied with one another to unify the country under their own leadership. The story centers on the Murakami Clan?commonly known as the Murakami Pirates?which effectively ruled the waters of the Seto Inland Sea, the principal transportation and shipping artery of western Japan.
Spectacular battles unfold in great detail on both land and sea. An endless parade of colorful warriors, a panoply of unconventional tactics (such as the weaponization of fireworks), and more offer readers the full excitement of battle in an era when wars were fought in close, hand-to-hand combat.
The heroine of the tale is a fictional character placed in the midst of true historical events. Kyo Murakami is the daughter of Takeyoshi Murakami, head of one of three branches of the clan and the man who lifted the fortunes of the Murakami Pirates to their current heights. In spite of this lineage, Kyo remains unmarried at 20. Tall and lean in stature, with a high-spirited and fierce nature inherited from her father, she is said to resemble Europeans in appearance and is therefore considered less than attractive. Ignoring the family precept that women must not set foot on military vessels, she takes great pleasure both in pursuing oceangoing scofflaws and in acts of piracy, and has declared that she’ll only marry another pirate. The unifying plotline of the story centers on the psychological growth of her character through her participation in a major battle.
The big event is the Battle of Kizugawaguchi, which takes place in July 1576. The monks of the Ishiyama Honganji temple in Osaka, the largest city in western Japan, have been extending their influence by organizing demonstrations by groups of the faithful. Lord Nobunaga Oda, one of the contenders for national hegemony, has been skirmishing with the Ishiyama monks for some seven years in an attempt to quash their influence. Now Oda forces have surrounded their temple-fortress, and food supplies are running short for the numerous monks and adherents holed up within.
The Mori Clan of southwestern Honshu receives a plea from the monks for delivery of 100,000 bales of rice, and turns to the Murakami Pirates to help with the task. A joint naval force of approximately 1,000 Mori and Murakami ships moves eastward. Meanwhile Oda forces seek the aid of the Manabe Clan, pirates based in the south of Osaka, to place a blockade at the mouth of the Kizu River to prevent the rice from reading the temple. Thinking better of directly confronting the rapidly rising Oda, the Mori-Murakami armada turns back, betraying the hopes of the Ishiyama defenders. But Kyo alone refuses to retreat, and opens hostilities on her own, which prompts the Mori-Murakami forces to reverse course once again and engage the Oda-Manabe forces in battle. The bitter, bloody fight rages on for hours, and Kyo survives repeated brushes with death, before heroically felling enemy general Shimenohyoe Manabe. The Mori-Murakami forces emerge victorious.