暗无天日 — “A state of utter darkness and oppression”

During the Kangxi reign of the Qing Dynasty, Zhu Hongxiang, the magistrate of Xuyi County, was promoted to Governor-General of Fujian and Zhejiang. He arrived in Guangdong and, within half a year, brought prosperity and eliminated malpractices throughout the province.

However, before Zhu Hongxiang's arrival in Guangdong, countless traveling merchants had died there, but no murderers were found, leaving behind numerous unsolved cases. For example, Zhu Zhaoyun and his servant perished; Wu Xueyi and his three servants died; Xie Junqing and his five family members were lost. In all these deaths, the murderers had cut open their victims' bellies, filled them with stones, and then sunk them to the bottom of the water.

It is said that as soon as Zhu Hongxiang took office, the local City God, recognizing him as an upright official, informed him that the aforementioned murders were committed by the old 'Dragon Boatmen'. Upon hearing this report, Zhu Hongxiang went to Longjin, a place in northeastern Guangdong, to apprehend the culprits. He arrested over 50 boatmen.

During interrogation, it was revealed that they used the pretext of ferrying merchants to lure guests onto their boats, then drugged them until they were unconscious. After that, they would cut open the guests' abdomens, insert stones, and sink them into the water. These boatmen formed a gang, causing an era of extreme darkness and lawlessness in that area.