"There are some contracts where you sign your life and you get your bones in return."
Seven ancient bronze coffins were discovered at a demolition site in the old city of Luoyang, arranged like a big dipper. There were no corpses in the coffins, only seven strange keys carved from human bones. Folklore consultant Meng Chan was invited to identify the bones, but found that the three red moles on her left shoulder blade resonated with the bone keys, causing severe pain in the collarbones of those who came into contact with them. The body of the first missing contractor was actually replaced with a bronze collarbone.
When criminal police officer Jiang Suo was investigating the case, he discovered that there was an unmarked monument hidden in his ancestral grave, and the clan rules required that he worship it every month. As marriage certificates and life-borrowing contracts emerged one after another during the Republic of China, the two uncovered a secret from 1942: seven couples used their bones as keys to borrow their lives from heaven. Now that the contract has expired, a new "locked lady" needs to be sacrificed - Meng Chan is the last of the bloodline.
When Jiang Suo smashed the ancestral lock stele and broke the bronze chains, he heard a voice chuckle in the darkness:
"The contract can be broken, but the bones cannot escape."
