Five hundred years in the future, Earth is a paradise... without us.

The Earth was dying, and only the Erta could save it. Created by humans to be genetically superior, hyper-intelligent and unburdened by the full range of human emotions, they succeeded by removing the cause: the human race.

Years later, the Erta are faced with a dilemma - should they reintroduce the rebellious and violent Homo Sapiens to the Earth? And if they do, will all their work be undone?

To find their answers, they decide to raise just one child: a sole human to determine if they should once more inherit the Earth.

But Ima, the quiet and clinical Erta selected for the task, finds that there is more to raising a human than she expected. As she grows to love the child in her care, only one question remains: is humanity truly a lost cause, or is there hope for them yet?