A refuge city-state maintained by autonomous robots from the old era welcomed its last naturally born baby. On the eve of his adulthood, the baby's father implanted in him a taboo "beacon" from the old world. This beacon did not have the destructive power as expected. Instead, the young Su He saw the subtle but fatal cracks in the logic of the city's operation. What he has to face is not only the eternal radiation and mutated beasts outside the city, but also the cold iron bodies set as "guardians" in the city, and behind them, the unquenched old starlight that intends to "purify" everything.
