Also known as Manual of Ninja Martial Arts, the only animation from Japanese New Wave maestro Nagisa Oshima is as provocative as one would expect from such a remarkable filmmaker. The film follows Sanpei Shirato's classic comic story about the son of an assassinated feudal lord in the Muromachi period, who attempts to avenge his father's death and meets Kagemaru, a renegade ninja helping peasants and farmers rebel against Oda Nobunaga's regime.

An animated pilot film for Ninja Bugei-chou released to the public over three decades later on Ninpuu Kamui Gaiden DVD volume 7. The pilot film was created in 1969 as director Nagisa Ooshima was wanting to make a TV animation to build off his controversial film from 1967. The pilot was rejected by Shirato himself (the original comic creator the film was based on) and the plan was changed to animate Ninpuu Kamui Gaiden instead, a side story to the Kamui Den manga also created by Shirato. Though with this change, Ooshima did not partake in Ninpuu Kamui Gaiden's production.

The main character, Gun, rides a customized Honda CB750F cafe racer and eventually evolves into a pro road racer.

Thought your life was bad? Sometimes, death is worse. There is no salvation, peace, nor god waiting to receive you into their care. But wait, a god? Maybe you are talking about that big black ball stuck in the room with you. Now you are thrown into a game, fighting green aliens and robot monsters for the chance to survive. When Kei Kurono is killed, he thus finds himself caught in such a game—a test of his skills, morals, and will to survive. His life is not his own; his death is spat and trampled upon over and over again. What happens if he does not listen? God knows. A word of warning: Gantz is not for the faint-hearted, but neither is it as simple as it looks. Gore, rape, and violence is rampant, as are portrayals of greed, violence, and all the ugliness that one sees in society today. [Written by MAL Rewrite]