In the late Jiajing period of the Ming dynasty when corrupt officials almost ruled the government, a secret police officer called Lu Yi, played by Ren Jialun, was ordered to investigate the missing of the funds earmarked for building river embankments in Yangzhou. He got help from Yuan Jinxia, a female constable of Liushanmen. They then became emotionally involved with each other. Later, they got accidentally drawn into multiple conspiracies....