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

At 2:30 AM, Xiao Li, the team member responsible for monitoring the surveillance footage of a convenience store near the east gate of North Plaza, suddenly shouted excitedly, "Team Leader Wang, we've found something!" All the team members immediately gathered around. Xiao Li paused the surveillance footage and pointed to a figure on the screen, saying, "Look, at 10:58 PM the night before last, this man appeared at the convenience store entrance. He was wearing a black hooded sweatshirt, a black baseball cap, and carrying a black backpack. His height and build perfectly match the suspect we've identified!" Although the footage was taken at night, the LED lights at the convenience store entrance were bright enough to clearly capture the man's figure. He lingered at the convenience store entrance for about two minutes, occasionally looking up and glancing around, seemingly observing his surroundings, before walking towards the taxi stand at North Plaza.

"Continue tracking his movements!" Wang Shuai's instruction was clear. Xiao Li immediately retrieved surveillance footage from other shops around the convenience store, piecing together the man's route: he emerged from a small alley on the west side of the North Plaza, crossed the pedestrian street, and finally arrived at the taxi stand at the East Gate, deliberately avoiding the main surveillance cameras in the center of the plaza, only moving along the edges of the blind spots in front of the shops. "This guy's counter-surveillance awareness is too strong; he's been avoiding surveillance from the very beginning," team member Xiao Wang remarked.

The focus of the investigation was concentrated on the taxi stand at the east gate of the North Plaza. Wang Shuai retrieved the public surveillance footage from that stand and, combined with supplementary footage from surrounding shops, finally reconstructed the entire process of the suspect hailing a taxi. The surveillance footage showed that at 11:02 PM the night before last, the suspect walked to the taxi stand and flagged down a red Santana taxi. He bent down and spoke a few words to the driver, after which the driver shook his head and drove away—clearly, he had been refused a ride. After being refused a ride, the suspect did not show any dissatisfaction but continued to stand in place, his eyes warily scanning the surrounding environment, seemingly checking whether any surveillance cameras had captured him.

At 11:08 AM, Zhang Tiancheng's green Jetta taxi slowly pulled into the taxi stand. Upon seeing it, the suspect immediately stopped it. He again bent down and exchanged a few brief words with Zhang Tiancheng before opening the right rear door and getting in. Zhang Tiancheng adjusted the rearview mirror and drove away from the stand, heading west along Binhe East Road—the same route previously observed in the surveillance footage. "That completes the picture!" Wang Shuai breathed a sigh of relief. "The suspect emerged from an alley west of Northern Plaza, deliberately avoiding surveillance cameras to reach the taxi stand. He was refused service the first time, but got into Zhang Tiancheng's car the second time, after which Zhang Tiancheng was murdered."

Based on the on-site investigation, a key investigative direction gradually became clear. Wang Shuai analyzed, "The suspect and Zhang Tiancheng had no prior contact. His actions of avoiding surveillance before getting into the taxi indicate that he had premeditated the crime. The loss of cash from Zhang Tiancheng, combined with the suspect's deliberate choice of taxis as his target, strongly suggests a murder-for-profit case. The suspect likely chose Zhang Tiancheng simply because he was refused service the first time he tried to hail a taxi, and Zhang Tiancheng was his second randomly selected target." This hypothesis highly coincided with the on-site investigation finding no obvious signs of revenge killing or crime of passion, and provided a new core direction for solving the case.

To identify the suspect, Wang Shuai immediately assigned two key tasks: first, to retrieve surveillance footage from all entrances and exits of the alleyway west of North Square to track the suspect's movements before entering the alley; second, to contact the driver of the red Santana taxi stopped by the suspect to understand the content of their conversation. However, the first task quickly encountered obstacles. The alleyway west of North Square is a typical passageway in an old residential area, narrow and lined with low-rise bungalows and old buildings. Apart from a blurry public surveillance camera at the alley entrance, there was no surveillance coverage inside the alley. Furthermore, the surveillance footage at the alley entrance showed that the suspect emerged from deeper within the alley, making it impossible to trace his earlier movements.

The search for the driver of the red Santana taxi was not without its challenges. There are nearly 200 red Santana taxis in the Chengbei District, most of which are individually operated and lack a unified dispatch platform. The team could only contact the taxi management department to retrieve the owner's information based on the taxi's license plate number captured in surveillance footage—京A·3Y289. After more than three hours of investigation, they finally contacted the owner and driver, Mr. Ma.

At 10:00 AM, Mr. Ma arrived at the Criminal Investigation Detachment. Upon seeing Wang Shuai, he immediately said, "Officer, did you call me because of the man who stopped my car at the North Square the night before last? I felt something was off about him; his eyes were sinister, and he was wearing a baseball cap that completely covered his face." "Tell me more about what happened. What did he say to you?" Wang Shuai pressed. Mr. Ma recalled, "Around 11:00 PM the night before last, I was waiting for passengers at the North Square east gate stop when he suddenly walked up to me and stopped my car, saying he wanted to go to Binhe West Road. I noticed he was wearing a hooded sweatshirt, a baseball cap, and a backpack; his attire was strange, and his voice was very low, so I couldn't make out his accent. I was a little scared, so I told him I had to pick up a pre-booked passenger and refused him. Looking back, I'm so glad I didn't pick him up; otherwise, who knows what might have happened."

"Did he specify which location on Binhe West Road he wanted to go to? Did he do anything unusual?" Officer Li asked. Master Ma shook his head: "He didn't say a specific location, just that he wanted to go to Binhe West Road. His behavior wasn't anything special, except he kept his head down, rarely looked up at people, and his eyes kept glancing around, like he was very nervous." Master Ma's description further confirmed the suspect's premeditated nature and strong counter-surveillance awareness, but no further valuable information about his identity was obtained.

Just when Wang Shuai's team was at a loss, the technical department brought important news. While recovering the damaged memory card from Zhang Tiancheng's taxi dashcam, technicians successfully extracted a fragmented audio recording. Although the video data was unrecoverable due to the damaged memory card, the audio recording clearly preserved the conversation between the suspect and Zhang Tiancheng. The audio was approximately 3 minutes long and contained concise content:
Suspect (in a deep, slightly hoarse voice): "Driver, to the intersection of Binhe West Road and Wanghe South Road."

Zhang Tiancheng: "Okay, fasten your seatbelts."

About 1 minute later

Zhang Tiancheng: "The checks on Binhe West Road have been stricter lately at night. Are you going there on business?"

Suspect (in a cold tone): "Yes, looking for someone."

There was no further dialogue until the audio cut off. (End of Chapter)