Based on the famous Thai epic poem, Kun Pan is the magical and tragic love story of Kun Pan's life. A jealous king sends Kun Pan to war believing he could win his beautiful wife, while Kun Pan dies on the battlefield. After a long time passes, the wife believes Kun Pan is really dead and agrees to marry the king. However, one day Kun Pan returns.

In the 1960s, there were few places on Earth as quiet and peaceful as Thailand's Chumporn province, This tranquility is shattered the day an unknown dead man's body is found along the banks of the river waterway. Soon after, villagers began to mysteriously disappear for no reason.

A police officer, a local guide and his daughter follow the trail of a prison escapee, Nasor, into a forest with many secrets, one of which relates to the death of Nasor's father by the father of the officer. As the group ventures deeper into the forest, the eerie realm unleashes its spiriits.