Matsudaira Sadanobu sends eight groups of Iga ninja to investigate the eight provinces of Kyushu following reports of smuggling .Tonbei, Kansai and Unosuke are assigned to Hizen. They infiltrate Shiranui Castle where they discover guns and gunpowder being distributed to other lords but one is wounded, one escapes to Edo and warns Shintarō before being killed while Tonbei searches for his wounded comrade.
