Ever since Nuwa refined five-color stones to mend the sky and cut off a turtle to stand up the four poles, the world thought that the sky and the earth were finally stable, but little did they know that the catastrophe that destroyed the heaven and the earth had buried deeper secrets between the heaven and the earth.
When patching the sky, the last five-color stone fell into the abyss of the East China Sea. The creative spiritual power contained in it was not dissipated, but actually gave birth to the "Essence of Breathing Soil" on the seabed, turning into a black spiritual fish that could understand human speech, and slept guarding the heart of the stone for thousands of years. The giant turtle whose legs were cut off by Nuwa was still alive, and its resentment condensed into "netherworld mist", lurking in the gaps of the three realms, secretly corroding the barrier of the Sky Mending Stone, vowing to return the world to chaos.
Thousands of years later, in search of her missing grandfather (a descendant of the Shoushi clan), the mortal girl A'gai strayed into the secret realm of the East China Sea, where she accidentally awakened the spirit fish and also disturbed the remnant soul of the giant turtle. The spirit fish told her: The barrier of the Sky-Mending Stone has been broken. If the "stone soul fragments" scattered in the world are not recovered, the turbid fog will swallow up the three realms.
A'gai embarks on a journey, and meets a white-haired old man who was transformed into a boy under Nuwa's throne, and learns the art of distinguishing stones. He also meets Cang Jue, a young man with Ao clan blood but a heart for the common people. From being suspicious of each other to fighting side by side, the two traveled through the ancient battlefields of Kunlun's remnants, human towns eroded by turbid fog, and underground caves connected to the netherworld. They not only had to fight against the monsters controlled by the remnant soul of the giant turtle, but also solved the "blank" used by Nuwa to mend the sky - why did she leave the last stone behind? And why did he "turn a blind eye" to Juao's resentment?
When A'gai gathered the fragments, she discovered that the secret of mending the sky was far from being summed up by the word "save the world", and that her own bloodline was inextricably linked to that ancient catastrophe.
