Zombie Silkworm Yin

Deep in the mountains of Lingnan, Linjiaao. Three hundred years ago, our ancestors used the witchcraft of "Bombo Silkworm Induction" to steal the dragon veins of the mountain people, and offered sacrifices to pure Yang boys every thirty years, in exchange for the prosperity of the clan. In his later years, the patriarch Lin Wanshan's only grandson was selected. He couldn't bear it, so he secretly replaced the zombie silkworms with medicinal silkworms and sacrificed them at night. His grandson was fine, but the villagers began to die mysteriously. The ancestral graves are cracked, the silkworms have become stiff, and the corpses of the former boys have awakened, sucking blood and claiming their lives. Wan Shanfang knew that his ancestral deeds were all sins, so he used himself as bait, burned caves in the mountains, burned evil poisons, and paid for his sins with death. The people surnamed Lin fled, the deep mountains became deserted, and children cried at night. Many years later, a young man returns with a fragment of the scroll and wants to restart Zombie Silkworm Yin. Is this to atone for his sins or to go deeper into the abyss?