Assassination—in Japanese, ansatsu or "dark murder"—was instrumental in the samurai-led revolution known as the Meiji Restoration, by which the shogun's military government was overthrown and the Imperial monarchy restored in 1868. The ideology and moral philosophy of the men behind the revolution—including bushidō or "the way of the warrior"—informed their actions and would become the foundation of the emperor-worship of World War II.

This first-ever account in English of the assassins who drove the revolution details one of the most volatile periods in Japanese history—also known as "the dawn of modern Japan."