Folklorist Chen Mo was forced to return to his hometown, Qishui'ao, shrouded in darkness. A bizarre accident in his childhood took away part of his memory and gave him a dangerous "synesthesia": he could sense the obsessions and fragments of death, but it was like gangrene attached to his bones. The seemingly peaceful village follows the ancient and cruel "yin law", and the living and the spirits are entangled in the invisible "yin contract".
Chen Mo uses knowledge as a blade, uses logic to reason about folk taboos, and takes risks to activate his synesthesia to spy on the truth, but he touches the deepest secret of the village. Qi Po knows everything but keeps it secret while the village chief Chen Kaijun tries his best to maintain the bloody "balance". The fragments of amnesia point to a terrifying dark contract that maintains the survival of the village, and Chen Mo himself may be the key node of the contract.
When the forbidden land is set foot on, the dust-covered tragedy reappears, and the terrifying force that maintains the Yin Law begins to "correct". Chen Mo must make a choice on the verge of collapse: inherit the shackles, become the new secret keeper, and endure the eternal shadow? Or risk everything to break the Yin contract and face the unleashed disaster? In the deep southwestern village full of ancient witchcraft and the struggle of human nature, every step he takes to uncover the secrets that are more terrifying than ghosts and gods.
