Humanity has always taken its home world for granted, and in the far distant future, mankind must abandon its home, Terra, in order to find new worlds for them to exist on. A lot has changed as the millennia went by, as all people are now the subjects of a supercomputer who rules over every aspect of life, including the right to reproduce. However, one group of people, known only as the Mu, still believes the old world of Terra still exists, and plan on doing what they can to get back home.