Attending ex-girlfriend's wedding, arresting the groom's officer on the spot

"This 'Fu' (福, meaning good fortune) character mark!" Wang Shuai felt a surge of excitement. "Perhaps we can start with this mark and check the surrounding lock shops to see if any of them have sold keys with the 'Fu' character mark!" Immediately, Wang Shuai gathered his team and told them about his discovery. The team members were also invigorated. Early the next morning, Wang Shuai led his team to check the surrounding lock shops again, this time focusing on whether they had sold keys with the "Fu" character mark.

However, the investigation results were still disappointing. Most lock shop owners said that keys with the "福" (Fu, meaning good fortune) character mark were a very common style, and many brands of locks had this type of key, making it impossible to pinpoint the specific shop that sold it. Just when everyone was about to give up, a lock shop owner near the North Third Ring Road said that he remembered a middle-aged man coming to his shop three months ago to have a key with the "福" character mark made, and he also bought a black leather wallet. "Are you sure?" Wang Shuai quickly asked. The owner nodded: "Yes, because the man chatted with me for a bit at the time, saying that he lived in an apartment complex not far from here and had accidentally lost his key, so he came to have it made. And the black leather wallet he bought is very similar to the style you described."

"Can you describe the man's features? What's the name of the neighborhood he mentioned?" Wang Shuai asked excitedly. The shop owner thought for a moment and said, "The man was about 40 years old, about 175 centimeters tall, of medium build, with short hair, and wearing a black jacket. He didn't say the specific name of the neighborhood, only that it wasn't far from here, in the northern suburbs." This information thrilled Wang Shuai; it was the most valuable clue they had obtained since the case was solved. Subsequently, Wang Shuai had his team retrieve the security camera footage from the lock shop. Fortunately, the lock shop's security equipment was relatively new, the footage was clear, and the recordings had been stored for a month.

The team carefully reviewed the surveillance footage from three months ago and indeed found the middle-aged man the shop owner had described. The footage showed that the man had come to the locksmith shop one afternoon three months prior to make a key and buy a wallet, a process consistent with the shop owner's description. Wang Shuai immediately instructed the technical department to extract facial features from the man in the surveillance footage, create a wanted notice, and circulate it throughout the city. Simultaneously, he arranged for team members to search all eligible residential areas in the northern suburbs near the North Third Ring Road in search of the man's whereabouts.

However, things didn't go as smoothly as expected. The northern suburbs have many residential areas, mostly older ones with high population mobility, making the search very difficult. The team searched continuously for a week, visiting more than 20 residential areas and nearly a thousand households, but still couldn't find the man. Even after issuing a request for assistance, they received no effective feedback. Although the case had shown a glimmer of hope, it quickly fell into a new stalemate.

Sitting in his office, Wang Shuai stared at the middle-aged man's face on the surveillance footage, a sense of helplessness washing over him. He knew this was the only lead he had; if it died, the case might truly become a cold case. Just as he was feeling hopeless, his phone rang. It was the technical department calling. "Captain Wang, good news! We conducted further tests on the fiber samples collected at the scene and found that the black fibers extracted from the area around the body matched the fiber composition of the black jacket worn by the man in the lock shop's surveillance footage from three months ago!" The technical staff member's voice was filled with excitement.

"Really?" Wang Shuai stood up excitedly. "That's great! This means the man in the surveillance footage is the deceased!" After hanging up the phone, Wang Shuai immediately gathered his team and told them the good news. The team members were overjoyed, their fatigue from the past few days vanishing instantly. "Now that we've confirmed the deceased is the man in the surveillance footage, we can start investigating his identity!" Xiao Li said excitedly. Wang Shuai nodded: "That's right! We'll immediately input the man's facial features from the surveillance footage into the national population information system for comparison, and at the same time expand the scope of our investigation, focusing on all businesses and units in the northern suburbs to find anyone who knows him."

However, reality dealt them another heavy blow. After entering the man's facial features into the national population information system for comparison, no matching identity information was found; a search of all businesses and organizations in the northern suburbs yielded no one who recognized him. This man seemed to have appeared out of thin air, without any identity information or social records. The case reached a stalemate again, and it was even more difficult than before. Although the deceased's physical characteristics were confirmed, his identity remained unconfirmed, and no one with any connection to him could be found, making it impossible to identify a suspect.

Wang Shuai felt unprecedented pressure. He knew that this case had attracted the attention of higher-level leaders, and if it couldn't be solved quickly, not only would he be unable to give an explanation to the deceased, but he also wouldn't be able to answer to the public. But he didn't give up. He firmly believed that as long as he persisted, he would definitely find clues. Subsequently, he adjusted the investigation plan, arranging for his team to continue investigating the deceased's identity while simultaneously reviewing all the clues from the crime scene investigation and interviews, looking for any overlooked details.

That day, Wang Shuai returned to the forensic department to examine the physical evidence collected at the scene. When he saw the bloodstained single-edged dagger, he suddenly noticed an extremely tiny scratch on the hilt, in addition to the complete fingerprints previously collected. This scratch was very well hidden and had not been noticed during previous investigations and examinations. Wang Shuai immediately instructed the forensic personnel to conduct a detailed examination of the scratch. Under a microscope, the forensic personnel discovered that the scratch was a very small "X" shaped mark, likely left accidentally during use, possibly due to friction with another hard object.

“This ‘X’ shaped mark might be a breakthrough,” Wang Shuai said. “We can check the surrounding knife shops to see if any of them have sold a dagger with this kind of ‘X’ shaped scratch, or if anyone has seen a similar dagger.” Wang Shuai then led his team to conduct another thorough search of the surrounding knife shops. However, the results were still disappointing. No knife shop had sold a dagger with this kind of ‘X’ shaped scratch, and no one had seen a similar dagger. The scratch was too small, and it was formed during use, not present at the factory, so the origin of the dagger could not be determined from this scratch. (End of Chapter)