Season 1 of The Haunted Chest premiered on April 1, 2019.

The story starts in the small Province of Chiang Mai where Koom Sai Karm is located. Euarngjun is a beautiful dancer with many men who desired her. She fell in love with the son of a millionaire, which leads to a chain of events and misunderstandings that resulted in her death. She was killed by being caged on a casket that fell in a lake. Nobody was able to find her. But her spiteful spirit is inside the casket, waiting to seek vengeance.

Many years later, there are rumors and tales about Koom Saai Karm and how there are ghosts. Many villagers met a ghost and their heads were pulled into the water. Every night at full moon, they would hear the drum and loom sounds.