Ji-Yeong and Ha-Joon find themselves sent to a magical Joseon by a dokkaebi named Kebbi. He says they are a surprise for his big sister, who happens to be Ji-Yeong’s missing friend, Si-Woo. Ji-Yeong is so happy to see her, but Si-Woo doesn't take the surprise too well. She had left the real world to live a new life in Joseon with Kebbi, where monsters lurk at every corner. They must survive until Kebbi can return the two back home.
