In a corner of the city where the neon lights don't shine, there is a "Spirit Detective Agency" that specializes in dealing with yin and yang matters. The boss Chen Mo can see ghosts, and his partner Fang Yang is good at "persuading" evil spirits through physical means. One rainy night, the female ghost Lin Wan's commission - to find the stolen urn - involved them in a huge conspiracy. They discovered that a force was systematically devouring souls, and the man behind the scenes was closely connected to Chen Mo's mysterious life experience. When his trusted teacher reveals his true colors and his close partner falls trying to protect him, Chen Mo must face his fate as a "gatekeeper". What he ultimately wants to solve is not how many evil spirits to eliminate, but how to calm down the obsessions trapped in the world, and find a way to the light for both humans and ghosts in despair.
