The Black King has a bridge repaired, while the human resistance plans to bomb the bridge when the enemy forces cross it. Meanwhile, Casshan and Luna are ambushed by robot scouts, which Casshan and Friender defeat; Casshan hacks into a scout and learns the Black King is initiating the Sigma Project to replace humans with Eco-friendly androids. While struggling with what to do, Casshan's mother appears to him and tells him to stop the Black King. Luna meets up with the resistance and Casshan stops them as the train crosses the bridge, but immediately regrets it. The bomb explodes too late, but Casshan redeems himself by destroying the train and vows to never again lose his way.
Far in the future, ecological disaster on Earth led humans to create a race of androids called Neoroids to clean up the mess but they promptly turned on their human masters and enslaved them. Enter a lone fighter named Casshan with a mission to free humanity ... and restore his family's honor.
