Convenience store No. 404 Is located in the gap between the human world and the underworld. It is an ordinary 24-hour convenience store during the day, and it becomes a supply station for supernatural creatures at night. There are power banks for zombies from the Qing Dynasty, selfie sticks for female ghosts from the Tang Dynasty, and Oden with the flavor of Meng Po soup. Cashier Zhou Xiaoman, an ordinary girl who can see ghosts, uses 502 glue and a sense of humor to deal with various supernatural events.