Five hundred years after Earth's environment was destroyed and the planet became known as Terra, humans have established a society in space that is entirely logical. Supercomputers govern the state, babies are cultivated in artificial wombs and assigned parents at random, and at age 14, children sit for an "Adulthood Exam." Humanity's greatest enemy is the "Mu"—humans who have evolved into espers. When Jomy Marquis Shin's birthday arrives and it is time for him to take his Adulthood Exam, he is shocked to discover that all his childhood memories are to be erased. Suddenly, he hears the voice of Soldier Blue, the leader of the Mu, urging him to hold onto his memories. Jomy escapes on a Mu ship and is shocked to learn that he himself is an esper and that the government has sentenced him to death. As his life nears its end, Soldier Blue transfers his memories to Jomy and names him the next leader of the Mu. Now, Jomy faces a choice: keep the Mu in hiding, or declare war on humanity to realize their dream of returning to Terra.