The Yellow Dragon Secret of Seeing a Coffin at the Bottom of the River

The night my grandfather died, the Yellow River bottomed out. A black coffin engraved with human figures was revealed on the river bed. A rusty iron chain was tied to the head of the coffin, extending deep into the mud. I am the seventh generation riverkeeper of the Chen family. Grandpa left me a nine-section whip and a sentence: "Enter the river at Yin time and seal the coffin at noon. If you don't wait for the time, there will be floods." I thought I was going to seal the coffin. I didn't expect to be in a coffin. In the coffin at the bottom of the river lies my father, who has been missing for eight years, and the secrets that have not been revealed for three thousand years under the Yellow River.