A young but seasoned Taoist from a powerful Daoist sect leaves home when his master sends him to the city to exorcise ghosts. After clearing two haunted houses, he is drawn into a string of bizarre incidents and challenged by rival practitioners from many countries, including a Thai sorcerer, Japanese Onmyoji, a Korean witch and Western exorcists. The action fantasy ONA is set in a world where technology and the supernatural overlap, and he battles demons and spirits there on his way to becoming a legendary Celestial Master.