Enslaved by an army of rebellious super-robots originally designed to help civilization avert a complete ecological cataclysm, mankind's only hope is Casshan, a legendary hero who wages a solitary war to defeat these Neoroids and restore the Earth to its rightful order. Ironically, Casshan's father is the same scientist who engineered the race of super androids now threatening to destroy all of mankind. On a crusade to clear the name of his father, Casshan must sacrifice his own humanity in order to attain the powers he needs to defeat mankind's powerful enemies. However Casshan's power does not come without a price. Haunted by the memories of his murdered mother and forced to deal with a super robot that has absorbed, and now manipulates, the consciousness of his father, Casshan must put aside his own emotions and fight to preserve the survival of the human race.