The cinnabar mining area in the mountains of southwest China has been abandoned for thirty years, and mercury poison has seeped into the rock formations and soil, but there are still villagers who can barely make a living by illegally mining tailings. Mining wife Lin Qiu lost contact with her husband for half a month after going into the mountains in search of "old mineral veins". She carried dry food on her back and a "peace charm" drawn by her daughter, and broke into a maze of underground tunnels.
The alleyway was filled with the smell of rust and putrefaction. Under the collapsed mine pillars, she encountered several crazy miners - their eyes were distracted, they repeatedly chanted "The red mist catches the soul", and they all had twisted snake-shaped symbols carved on their wrists. The villagers advised her not to seek death, saying that no one who entered the mountain ever came out alive, but the half piece of silvery mineral crystal left behind by her husband became the reason why she refused to look back.
As she went deeper, Lin Qiu discovered that there was something fishy about her husband's disappearance: there were fresh marks on the alleyway wall, and her husband's safety helmet was still left in an abandoned work shed, with dark red stains on it that were not mercury poisons. She gradually understood that there was something more terrifying than mercury poison hidden deep in the mining area - the truth about the mining accident ten years ago, and the people who wanted to cover up the truth forever. She must find her husband before the poisonous fog spreads out of the alley, and she must get out alive with the truth.
