Arlong, Eight Years Prior

On a day when their household is distracted by their mother's sudden illness, Nezha is left in charge of his younger brother, Mingzha. Tempted by rumors of treasures and mysteries, Mingzha begs to approach the forbidden grottoes of the Nine Curves River. Nezha reluctantly agrees to look from a distance to keep Mingzha safe while proving his own responsibility.

Drawn closer, they spot what appears to be their father Yin Vaisra's cloak on the riverbed, identifiable by the House of Yin crest. As Mingzha edges toward a cave mouth, a chilling dread seizes Nezha. The water ripples; a vast, serpentlike shape erupts, and a wave slams Nezha underwater.

Submerged, Nezha finds the shallows impossibly deep and silent. He sees a pale green light illuminating eyeless human faces set in sand and coral amid an expanse of coins, porcelain, and gold stretching into the grotto. A dark movement flickers and vanishes as Mingzha’s distant screams cut through the silence.

Nezha fights to the surface to find the water shallow again, now streaked with blood and remains. He discovers Mingzha’s golden anklet, then confronts a rising dark shape by the caves. A disembodied voice greets him—“Hello, little one”—and Nezha screams, marking a devastating and supernatural loss.