Jushichinin no Ninja plot
"A film as hidden as the ninja"
Edo Castle, September 1631. The shogun is terminally ill and his son Iemitsu is first in line to become the new shogun. However, Tadanaga, the younger brother of Iemitsu, also wants to become the new Shogun. To this end, he makes pacts with the Tozama lords. After his father's death, he plans to attack Edo and take the Shogunate for himself. A group of seventeen Iga ninjas led by Jingoza, the Iga Ninja Group Three, are sent out to steal the pacts in order to expose the plan and force Tadanaga to commit suicide. They must face the cunning Magokuro Saiga and his hired Negoro ninjas.