The Nameless City Between Two Rivers: Eternum, Part one - Eternum, #3.1

A clay tablet enters the archive with one impossible flaw: its weight is wrong.
In the Tablet Library of Uruk, every debt, death, offering, boundary, and royal name is preserved in fired clay. Namsin, a junior scribe trained to trust the record above all things, discovers an older text buried beneath an ordinary tribute account. A dead king's name has been written again and again across centuries. Beside it are water-gate numbers, erased seals, and the quiet arithmetic of missing people.
To report the anomaly would be safe. To ignore it would be lawful. But Namsin has spent his life knowing what it means when a person is reduced to a number, and the tablet before him is not a mistake. It is an account still being kept.
As black water begins moving through sealed channels beneath the city, a water-gate engineer, a Low City widow, and a river ferryman are drawn toward the same forbidden pattern. The Temple calls it procedure. The palace calls it order. The records call it continuity. Yet behind the city's splendor, names are vanishing, rituals are changing, and something ancient is pressing against the boundary between archive and grave.
In Uruk, the dead do not return by miracle.
They return when someone writes them back.