My name is Shen Luo, and I'm keeping vigil at Yizhuang.
Master established three rules: don't answer the knock on the coffin in the middle of the night; don't open the coffin if you hear a noise; don't look back no matter what happens.
That night, there was a "deep" knocking sound from the third coffin, which lasted until dawn.
When the coffin was opened after dawn, the old woman lying inside had broken nails and scratches on the inside of the coffin lid - she had been buried alive.
Master said: "How do you know that the person knocking on the coffin must be the person in the coffin?"
Six coffins, six unsolved cases, six lives.
Dead people can't lie, but living people can.