It is the year 2050. Derrida Yvain, a young engineer, rose to prominence as a result of his contribution to the creation of the "Autonomous Machine DZ" at Rebuild, his father's manufacturing firm. Derrida and his coworker Nathan uncover a defect in the DZs one day and try to alert their employer, but they are disregarded. Although Derrida and Nathan are aware of the risk, they choose to postpone any action in order to attend Nathan's daughter Mage's birthday party. After a calm day, Derrida and Nathan are unexpectedly ambushed by unknown attackers the next day. At the conclusion of his escape, Derrida falls into a cold sleep machine and wakes up 10 years later in a destroyed world.