This is a Thai movie based on a Thai folktale of a shaman who can shape-shift into a wild animal.
In one scene we hear a story that is also shown on film:
"Two poor farmers once met a little monk.
The monk asked them, Do you want to be rich?
The two farmers said, Yes.
He told them to go to the pond and collect rocks from the water. Then he disappeared.
The two farmers did as he said. They filled their bags with rocks.
One man's rocks turned to gold, while the other's turned to silver.
They both wanted more so they went back to the pond. But this time they only found rocks.
The gold and silver turned into toads that jumped away."