Shogun Assassin

Shogun Assassin is a movie starring Tomisaburô Wakayama, Kayo Matsuo, and Minoru Ôki. When the wife of the Shogun's Decapitator is murdered and he is ordered to commit suicide by the paranoid Shogun, he and his four-year-old son...
A Shogun who grew paranoid as he became senile sent his ninjas to kill his samurai. They failed but did kill the samurai’s wife. The samurai swore to avenge the death of his wife and roams the countryside with his toddler son in search of vengeance.