In the near future, an amnesiac Casshern fights anti-human robots on a desolate Earth. Most of the humans were killed in an apocalyptic war when he was serving under the direction of Braiking Boss after he assassinated a girl named Luna. During his quest to find out who he is, Casshern befriends a human girl named Ringo. However, Ringo finds herself to be scared of Casshern after he kills a robot who was trying to attack her. Not long after, he faces against an anti-Casshern mercenary named Lyuze.
In un futuro prossimo, un androide di nome Kyashan vaga su una Terra desolata. La maggior parte degli esseri umani furono uccisi in una guerra apocalittica dai robot guidati da Bryking Boss. Durante la sua ricerca per scoprire chi sia, Kyashan fa amicizia con una bambina robot di nome Ringo.
自分がなぜ襲われるのか、そして自分が何者であるのかさえもわからないでいた青年は、浜辺で少女と出会った。リンゴと名乗るその少女との触れ合いの中に、ひと時の安らぎを覚える青年。名を聞かれた彼は、襲ってきたロボット達の言葉を思い出し、自らをキャシャーンと名乗る。だがそこへ再び一体のロボットが現れて…。
