In the slums of Zero City, a sprawling metropolis ruled by machines, a poor orphan gril huddles in the dark with her computer hacking brother. The machines watch over everything, silencing expression and crushing dissent under an iron fist. After a fateful encounter with Zero City's robot sentinels, Yoshimi learns that she'll need to be strong to survive this world. And the machines will soon learn that the human spirit is not so easily broken...