During a rare moment of peace, Casshern presses Ohji for the story of Ringo’s origins. Elsewhere, Dio and Leda cross paths with two deadly robots that were once the strongest of their kind.

Casshern desperately seeks to unravel the mystery of his dark past. An altercation with Dio, his robotic mirror image, could provide answers to his many questions - or at least get him killed.

Dio’s mission to assemble a robot army is interrupted by the appearance of Dune, a formidable warrior who was once Luna’s bodyguard. Elsewhere, Casshern continues his search for Luna.

Dying robots far and wide herald the saving grace of Luna. Meanwhile, Lyuze is disturbed to notice that Ringo has begun to rust, and Casshern is confronted by the monster who ordered him to Ruin the world.

Ringo’s attempt to comfort Casshern leads her into a deadly trap. Ohji is quick to come to her rescue, but for them both to escape alive, Casshern must fight Dio as Braiking Boss looks on.

Casshern and his traveling companions befriend three children claiming to be descendents of Luna. When the youngsters are attacked by Leda, Casshern risks his own life to protect them.

Casshern, Lyuze, and Ringo finally reach Luna’s castle, where they find countless robots hoping to be spared from the Ruin. Dune is among their ranks, but Luna’s treatment of her former protector is shocking.

Luna asks Casshern to serve as her new guardian; Lyuze and Ringo lose faith in the promise of salvation; and Ohji returns with disturbing revelations about the Sun Who Was Called Moon.

Leda tries to convince Dio to accept Luna’s healing, but eternal life is no longer his obsession. Dio now lives only to fight Casshern - even if their battle ends in his own destruction.

Casshern and Dio continue their epic final battle. Although only one will survive, they’ve embraced the chilling reality that fighting is the sole purpose of their tragic existence.