In a dystopian future, Japan is a country devastated by war and disease, where humanity faces an impending collapse. Amid this chaos, a young man named Tetsuya, the son of a famous scientist, finds himself at a moral crossroads when his father embarks on bold experiments in an attempt to save humanity. However, his experiments invoke the creation of powerful cyborgs that, instead of serving humanity, end up unleashing an unstoppable war.
Desperate to save his beloved Sōko, who has fallen victim to the war, Tetsuya volunteers to become a cyborg, transforming into an immense combat machine with superhuman abilities. But as he embarks on his new existence, Tetsuya grapples with the emotional conflicts of his new identity and the consequences of his transformation. With war raging around him, he becomes the target of a group of rebels seeking to put an end to the tyranny of the government and the failed scientific experiments.
The story delves into Tetsuya's internal struggle as he navigates between the humanity that still resides within him and the cold logic of his new form. This blend of relentless action, philosophical reflection, and stunning visuals turns his journey into an epic odyssey of self-discovery and redemption, where every decision could determine the fate of the few survivors left in his world.