Zhang Hua's Story

On a rainy night, Zhang Hua, who had been unemployed for 14 months, picked up a rusty knife among the demolition rubble. Two hours and forty minutes later, three people were dead and he was caught red-handed. The evidence was overwhelming, the confessions were made, and the case should have been closed quickly. However, detective Chen Ming discovered that the wounds of the three deceased were almost identical. The surveillance system failed one after another when the murder occurred. The knife interfered with the signal, modified the slash, and even injected some unknown substance into the human body. This is not a murder weapon, but an experimental instrument that has been maintained for more than thirty years. When the "Blood Knife Case" twenty-four years ago resurfaced, a codename that had been hidden for many years gradually emerged: 706. But the real question is not what the knife made Zhang Hua do, but - when a person can still stop, but finds that committing evil is "no longer difficult", who exactly belongs to the responsibility?