Futaro Yamada (1922–2001), born Seiya Yamada, was a Japanese novelist. A native of Hyogo Prefecture, he began writing mystery fiction while studying at Tokyo Medical University and received the Mystery Writers Club of Japan Award for Short Fiction in 1949 for “Ganchu no Akuma” and “Kyozo Inraku.” He worked across mystery, historical fantasy, and fiction set in the Meiji era, and established the influential “Ninpocho” series, whose characters wield elaborate and often supernatural ninja techniques. In “Koga Ninpocho,” ten Koga and ten Iga ninja are drawn into a lethal contest linked to the Tokugawa succession, while the doomed relationship between two heirs from the opposing clans gives the conflict its emotional center. Yamada received the Japan Mystery Literature Award in 1997.