Adapted from Sanpei Shirato's classic manga, a legend unfolds as Watari, a young boy skilled in ninjutsu, takes on the corruption inside the Iga clan and avenges many unjustly killed ninja by the acts of Sandayu Momochi's scheming vice-leader.

Movie adaptation of the 1959 ninja novel. With war against Korea looming on the horizon, Hideyoshi Toyotomi, the 'Taiko' becomes the target of an assassination attempt to be carried out by the Iga Clan of ninja spies. Master spy Juzo Tsuzura (Ryutaro Otomo) is assigned the task, but first he must defeat a former Iga spy who has become a traitor, and outwit the treacherous woman that is trying to seduce him.