Yumika's death sentence brings turmoil to Iga. As Acting Chief, Ittoki's leadership is tested, but he is still in shock over his mother's imprisonment. Meanwhie, in Koga, something fearsome is beginning to move.

Ittoki heads off to settle scores with Onimichi and Onimichi sends all his forces to Iga to exterminate the Iga villages. The final battle of the Shinobi begins.