One day, the Zhangcheng City Public Security Bureau received an unsigned envelope and asked Lu Feng, the Criminal Investigation Captain of the Municipal Public Security Bureau, to collect it. There was no sender or address, as if it appeared out of thin air. Even the surveillance did not capture the person who sent the letter. The things in the photos began to happen in reality. He took out the photos and looked carefully, only to find that every case was interrelated and entangled. The world was like being entangled with an iron chain...
However, one day, he discovered that what happened before suddenly happened again one day...
