In October 1994, a major murder occurred in a hair washing room in Xicheng City that killed three people. The criminal police detachment has been supervising the case for many years, but there has been no progress. Shi Qiang, an office clerk, was temporarily assigned to the task force and discovered a breakthrough clue by chance. It seemed that someone was hindering the investigation of the case behind the scenes. Who had the problem? Is there a mole inside...
