The landowner Simen Naо from Gaomi, located in the northeast, was executed and unjustly accused. The lord of the underworld, Luo Wan, was unable to force him to confess his sins and decided to send Simen Naо back into the world of the living for a new birth in a human form. However, before that happens, he must go through a series of reincarnations in the bodies of various animals—such as a donkey, an ox, a dog, a pig, and a monkey—in order to rid the hatred in his heart.