One night, Ningzi and Naiyu returned to their childhood appearance. And in the organization Naiyu belonged to, countless people were hunting them down. People in the organization often kill people to lure Ningzi and Naiyu to appear, because Ningzi is a female detective. In each thrilling case, Ningzi met people in the organization from time to time. They all became smaller because the organization no longer needed them. And this is what gives Ningzi more power - people who are not wanted by the organization join her team. But in the end, how could anyone laugh quietly in a coffin underground?