The story takes place in the pre-liberation southwestern borderlands, where two well-dressed young men are welcomed on a winding path in the deep mountains. They are Qi Yuanjing and Zhou Luo, spies sent by the police department, disguised as merchants to find out the reality of a group of cunning bandits. As twilight approaches, the two men make their way to the secluded Purple Cloud Taoist Temple. The Taoist master, Shou Jing, shows the two of them in, but the meticulous Qi Yuanjing discovers a series of suspicious things inside the Taoist temple. The Taoist master blinks at the queries raised by Qi. Before long, they saw horrific ghostly figures in a nearby attic. According to the Taoist priest's account, a tragic war once took place here two hundred years ago, so whenever it rained, ghosts would come out and roam around.