Makoto 'Smile' Tsukimoto and his friend Yutaka 'Peco' Hoshino have been playing table tennis together since they were kids, but as they enter high school, they find that the game, and how they see it, has changed. Peco, brimming with confidence and energy, wants to be the best in the world, but the reserved Smile has little fighting spirit and doesn't want to sacrifice others' happiness just to win, despite his innate talent. As the two grow, and experience the ups and downs of the sport – and life – they try to figure out exactly who they really are and what drives them to play.

After the murder of Luna, the robot society that rules the planet starts to rust and decay. Death and despair spread through the land like wildfire. The only one unaffected by the affliction that becomes known as "The Ruin" is Luna's assassin, Casshern. Unable to remember if he really triggered this capital sin against the entire mechanized civilization, Casshern embarks on a journey to unravel the mystery that connects him, Luna, and the plague.