In the supernatural world where hundreds of ghosts walk at night, high school student Zhang Di accidentally learns that his grandfather Zhang Kui'an is rebelling in the underworld. He also awakens his negative emotional system and becomes stronger by making others break through their defenses. He learned the special paper-burning technique and sent Gatling and other strategic materials to his grandfather, forming a Yin-Yang strategic cooperation. During this period, he teamed up with the female ghost and the paranormal investigation bureau to catch ghosts and eliminate evil spirits, deal with campus murders, ghosts taking possession of the body and other crises, and earn a lot of negative emotion points to unlock multiple skills. In the end, he revealed his true identity as Emperor Fengdu of Beiyin, and in order to regain the Ghost Seal and rectify corruption in the underworld, he started the ultimate showdown between Yin and Yang.
