The story takes place near the end of a fictional ancient dynasty, when a mysterious plague known as the “Rotting Plague” suddenly breaks out. Those infected lose all reason within three days and become bloodthirsty, violent “Plague Wraiths.” They possess extraordinary strength and speed, but their intelligence deteriorates. The true source of the plague is a biological weapon secretly developed by the imperial court to eliminate its political enemies. When an experiment goes out of control, the plague spreads across the country. The court publicly organizes relief efforts, but in secret it hopes to use the crisis to reshuffle the balance of power.
