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.

The fifth and final installment with the build up of the epic battle between Sasaki Kojiro and Miyamoto Musashi. With all the familiar characters making appearances: Otsu (Musashi's great love), Akemi, Matahachi (his former fellow soldier), old lady Osugi (still doggedly trying to defeat Musashi), and even the return of Priest Takuan (the man responsible for his journey towards enlightenment). But most of all, the boastful, long-haired and long-sworded Sasaki Kojiro.