The introverted and honest high school student Jun Tendo (voiced by Kensho Ono) grew up in the beautiful and comfortable Kyoto. One day, he was suddenly attacked by an evil ghost. He ran into an ancient temple in a panic and was rescued by the monk Yuanyun (voiced by Shido Nakamura). Suddenly, he was brought to the distant Heian period by Yuanyun. It turned out that evil ghosts were rampant in the Heian period and fought a series of wars with humans. In order to eliminate hungry ghosts, Yuanyun traveled through time and space to bring Tendo, who was called the savior. In the latest battle, Tendo accidentally awakened the Yamata no Orochi, which claimed to be able to destroy evil ghosts, in order to rescue his partners. By chance, he and the snake rescued the evil ghost Shuiye who was being hunted by the nobles, and thus discovered the true face of the evil ghost, and his belief as the savior was also shaken... This film is adapted from the original work of the same name by Takashi Takata.