Chapter 35: I can attempt to reconstruct the travel trajectory!

In the restroom of the Shen family village in Chaoyang, Shen Ting stood washing up while frowning at the map uploaded by the trio—Jigsaw, Hannibal, and Yoshikage Kira—in the criminal investigation group chat.

It wasn't that the three hadn't managed to pinpoint potential criminal hideouts; on the contrary, there were far too many locations circled. Last time, each of them had only identified three suspicious vehicle-dumping sites, and those had overlapped. This time, however, each had marked seven or eight spots, and most did not coincide. Investigating them one by one would mean checking nearly twenty locations. The sheer workload was daunting.

Hannibal: "It is normal that the locations do not overlap. As Jigsaw previously noted, the criteria for a base are fundamentally different from those of a dumping ground for bodies or vehicles."

Yoshikage Kira: "The point is that the requirements for this base are very low. The criminals might have only visited it once or twice over that half-month period, unlike the vehicle-dumping site, which had high requirements."

Jigsaw: "With low requirements, everyone’s standards for choosing a base naturally differ, which inevitably leads to divergence."

Shen Ting nodded, understanding their point. The problem was that if they had to investigate every location the three had marked, they would run out of time. The task had been issued four days ago at noon, and the deadline was five days. It was now early morning; at most, they had only one full day and six hours remaining.

"Furthermore," Shen Ting thought, "the three of them don't seem particularly certain in their words. These locations might not even be the criminals' base." It was possible the criminals didn't even have a base. Yet, after some thought, he realized there were no better options.

After dropping off his sleepy daughter, Shen Manman, at kindergarten, Shen Ting headed toward the Chaoyang Police Station. On the way, he redeemed "Palynology," consuming ten skill points and leaving him with only two. As he absorbed the knowledge of pollen analysis, his confidence grew. If the perpetrators truly had no base, then it was simply bad luck. But as long as there was a base, with the support of palynology, he was eighty to ninety percent sure he could find it. In particular, even if the pollen found in the Hummer was fragmented or degraded, the techniques he had just acquired were sufficient for identification, provided the state wasn't excessively deteriorated.

He parked his electric scooter at the police station. Upon arriving at the office, he learned that Zheng Yuanqiao had called for another case review meeting. Shen Ting walked straight into the conference room of the First Brigade. The moment he stepped inside, he saw that the officers and young detectives alike looked as wilted as frost-bitten eggplants. They all had dark circles under their eyes, looking like human pandas. It was clear they had spent the entire night reviewing files and discussing the case. They were pushing themselves too hard.

By comparison, Shen Ting, who had slept soundly all night, felt so energized that he felt a bit guilty. He secretly tousled his hair into a mess and let his eyelids droop, trying to look like he had stayed up all night worrying about the case.

Once everyone was seated, the meeting began. Zheng Yuanqiao asked everyone to share their thoughts on the case. They each offered their opinions and proposed various investigative ideas, but Shen Ting felt that their suggestions were too peripheral and lacked feasibility. For example, one person suggested reviewing surveillance footage from the two weeks following the incident to track the criminals leaving the cordoned-off area. The problem was that no one knew the number of criminals, their appearance, or their gender. There was simply nothing to track. This further highlighted the cunning of the criminals. Through eating ears, deliberate typos, and meticulous planning, their image had remained blurred, likely to disrupt the police investigation.

Zheng Yuanqiao could tell that the ideas were not reliable; calling them "thinking outside the box" was a stretch. "These methods won't work. Does anyone have other ideas?" Zheng Yuanqiao scanned the room, but no one spoke. Finally, he looked at Shen Ting, and seeing no reaction, he sighed inwardly. Ever since Shen Ting found the Hummer, Zheng Yuanqiao felt he had been harboring unrealistic expectations for him.

He was about to declare the meeting adjourned when a hand was raised quietly. Zheng Yuanqiao looked over and felt a surge of surprise. It was Shen Ting.

"Shen Ting, you have an idea? Please, speak your mind," Zheng Yuanqiao said with a smile.

Shen Ting gathered his thoughts: "Captain Zheng, my idea is quite simple. Given the current status of the case, it is unrealistic to expect a breakthrough through physical evidence or other clues to identify the culprit immediately. A more practical goal would be to find a way to determine the vehicle's trajectory at the time and attempt to locate the places where they stopped."

The people in the room nodded. Everyone understood that this approach was based on the most critical piece of evidence: the Hummer. The criminals must have used the Hummer to move around within the blockade. Now that the Hummer had been found, the most obvious evidence was the sand and stone samples collected from it. A more subtle, yet vital piece of evidence was the vehicle's trajectory. In a murder case, a car's path is crucial evidence, potentially revealing the criminals' residence, lifestyle, and occupation. However, because the Hummer's dashcam had been destroyed, they could only rely on the physical evidence within the car to reconstruct the path.

At this, the officers frowned. The logic was sound, but the problem was: how to reconstruct the trajectory? Based on what evidence? A technical staff member shook his head: "We already tried this, but it doesn't work. The most common way to reconstruct a trajectory is by using the sand and stone on the tires. But the criminals cleaned the tires, and the remaining debris lacks specificity. You might not know that to determine a trajectory within a small area using sand, you need to correlate it with mixed-in fibers, paint chips, glass shards, and so on. There are too few of these substances in the tire treads to reconstruct a path."

"The insect remains are too decomposed," another added. "Even if they weren't, it's difficult to use insects to determine the trajectory of a car within a local area."

"The pollen inside the car could work," someone else noted, "but it suffers from the same problem as the insects. Twelve years later, there is too little left. Otherwise, we could have hired a palynology expert to try and reconstruct the path. Our technical team considered all of this long ago."

Zheng Yuanqiao frowned deeply. Was Shen Ting's idea also a dead end? Would this case have to be shelved again? Thinking of the sorrow in Liu Qitong’s eyes and the cries of the victims' families, Zheng Yuanqiao felt a sense of frustration. He instinctively took out a cigarette but, noticing the non-smokers in the room, didn't light it, merely holding it to his nose to smell it. The other officers were also silent, brows furrowed.

"Ahem."

Suddenly, a dry cough broke the silence. It wasn't loud, and it sounded somewhat hesitant, but in the pin-drop silence of the conference room, it resonated like a booming bell. Everyone looked over to see Shen Ting raising his hand again.

"Um, Captain Zheng, what I meant by that suggestion is that I can actually attempt to reconstruct the Hummer's driving trajectory myself."