 When Britannia invaded Japan, he went into hiding with his sister, taking refuge with the Ashford family.Seven years later, he discovers C.C., who grants him a Geass that allows him to command any person to follow his subsequent order.Seeking to build a peaceful world for his sister even though all she wants is to be with him, he begins to orchestrate a revolution, pursuing the destruction of Britannia under the guise of his masked alter-ego, Zero.