Chapter 7

Mobei City Public Security Bureau, Criminal Investigation Division.

In the office, Wen Sibao was reading a forensic report on recent cases prepared by the Forensic Team. A particularly striking conclusion in the report caught his attention:

-Based on the degree of rigor mortis, corneal opacification, and the extent of livor mortis at the crime scene, the estimated time of death was about 6 to 8 hours before the scene was discovered.

A young female forensic doctor asked, “Senior, during the period when the victim died, the suspect has a solid alibi. Could we really have arrested the wrong person?”

Wen Sibao sat up straight, his gaze intense as he stared at the photos of the deceased. “Impossible. There’s no way we’ve caught the wrong person! I can tell just by looking that the suspect isn’t telling the truth. There must be a mistake somewhere between the time of death and his alibi!”

This young forensic doctor was Li Mengxue, two years junior to Wen Sibao at the Police Academy. Since her first day at the academy, she had felt a subtle admiration for her Senior. Hearing his words now, she couldn’t help but feel a trace of doubt about Wen Sibao’s judgment. Yet despite her doubts, she still firmly believed in him-an inexplicable sense of trust.

Sitting next to Li Mengxue, another recently graduated young man muttered unhappily, “This time the report was personally prepared by Mengxue’s master, who had already stated that when the victim was found, there was not only whole-body rigor mortis and the livor mortis hadn’t reached its maximum, but the corneas also weren’t fully opaque. How could there be a mistake…?”

“Quiet!” Li Mengxue reprimanded her apprentice softly. “Xu Wudi! Don’t speak!”

Xu Wudi, a newcomer to the Forensic Team this year and Li Mengxue’s apprentice, had once aspired to be a dentist wielding pliers. In his simple mind, every organ in the human body comes singly or in pairs, but there are 32 teeth, or 36 with wisdom teeth. Believing in the principle that more is better, Xu Wudi saw dentistry as the most lucrative profession of the future. After the college entrance exam, he firmly applied for the city’s Medical University’s Stomatology program. Unexpectedly, when filling out the application, he saw an option to “opt to accept reassignment.” Not understanding what “reassignment” meant, he only recognized “accept.” Concerned that his scores weren’t ideal and fearing he wouldn’t get into the Medical University, he simply checked “accept,” expressing his determination to become a dentist.

As a result, when the results came out, Xu Wudi was inexplicably assigned to the Forensic Medicine program, which every year takes students with lower scores.

After starting work, Xu Wudi-living up to his name-considered himself unbeatable and acted with reckless abandon. Once, during a meeting, he challenged the Political Commissar in charge of ideological work at the Public Security Bureau so fiercely that the man almost had a heart attack. Since then, Xu Wudi became something of a legend in the department and justifiably earned the nickname “Invincible.”

Despite his “invincible” nickname, Xu Wudi only listened to Li Mengxue within the team. Now, after being scolded by his master, he dared not say more, but still felt dissatisfied with Wen Sibao’s judgment, thinking Wen Sibao didn’t trust his master’s assessment, and grumbled quietly.

Wen Sibao put down the photos and said to Li Mengxue, “This suspect is extremely cunning. I’ve been thinking, if I were the murderer, what would I do to create an alibi?”

Li Mengxue asked, “So, Senior, you mean…”

Wen Sibao met her gaze. “Not only do I trust your forensic results, I trust your judgment even more. But precisely because of this, I think the suspect must have used some method that led your Forensic Team to misjudge the time of death.”

Suddenly, Wen Sibao’s breathing quickened, his eyes seemed to blaze as he stared at the photos, raising his voice, “I think I’ve found something! You two, come and look at this!”

Wen Sibao pointed at a photo from the crime scene. “Look at this bloodstain beneath the body.”

In the photo, the blood beneath the victim had long since dried and seeped into the floor. Judging from the marks, the large pool of blood had formed an irregular shape, with several thin streaks drawn out from the edges.

Xu Wudi glanced at the photo and replied immediately, “What’s wrong with this blood? With so much blood here, it must be the primary crime scene!”

“You’re right, this is indeed the primary crime scene,” Wen Sibao continued. “But do either of you remember what the weather was like on the day of the crime?”

Li Mengxue said, “Let me think. I remember that when we found the body, it was in the afternoon. The weather was stuffy and hot. The Forensic Team’s van had a broken air conditioner, and Invincible got scolded by the Group Leader for complaining about the heat.”
Wen Sibao nodded and continued to explain, “Now, this is very strange. Since there was no wind all day and the weather was extremely hot, why would the blood beneath the body show such traces?”

Upon hearing this, Li Mengxue immediately understood. She hurriedly checked the photo again and exclaimed in surprise, “Ah! I get it, Senior, you’re right! If there hadn’t been windy weather, the blood would have naturally pooled into a single patch at the edges, gradually spreading outward. It couldn’t possibly look like the traces we see now! Only during strong winds would the blood on the ground form several irregular streaks, which is exactly the Rake Pattern we see around the deceased now.”

Wen Sibao nodded affirmatively. “So the problem really lies here. I just checked the weather report for that period. There was only a Sandstorm the day before the incident, with wind speeds reaching level 6. The rest of the time, it was clear and windless. Based on this, I believe the actual time of death was about 24 hours before the case was discovered, that is, during the windy day before.”

“But…”

Although the Rake Pattern of blood around the body in the photo was enough to indicate the weather conditions at the time, Li Mengxue still asked in confusion, “If the time of death really exceeded 24 hours, then the Livor Mortis, the degree of rigor, the level of decomposition, and the chemical reactions in the internal organs shouldn’t have matched what we observed during our examination.”

“You’re absolutely right! But this is exactly where the killer tried to mislead us-and it’s also the boldest part of their plan!” Wen Sibao took out another photo of the deceased on the autopsy table. On both sides of the victim’s body, between the deltoid and pectoralis major muscles, there were two dark red marks, each less than 1 cm wide. He explained, “I’ve been thinking about this from the beginning. No matter how you look at it, these two red marks look like creases, and the skin at the creases also shows signs of external force tearing. Similar marks also appeared on the inner thighs and calves.”

Li Mengxue asked in confusion, “Creases? Are you suggesting these are creases left by the victim curling up? That can’t be right. Such creases would only occur if the body was subjected to external force and kept in a curled position for a long time, but it’s hard to imagine how that would cause the tearing of the skin we see now.”

“That’s exactly the issue!” Wen Sibao said. “I have a bold hypothesis: the killer murdered the victim a day earlier, then, growing increasingly fearful, returned to the Primary Crime Scene and took the body away, storing it in a cold storage. After freezing the body in a sack for more than ten hours until it was completely stiff, the killer had an accomplice bring the body back to the Primary Crime Scene and waited for it to thaw. However, the accomplice probably wasn’t very composed, so before the body had fully thawed, they forcibly straightened the curled-up corpse. At that moment, the skin’s surface still had the stickiness caused by freezing, which is why tearing marks appeared on both shoulders, as well as the inner thighs and calves.”

Wen Sibao paused, then continued to explain, “The killer’s accomplice would need to wait about 2–3 hours for the body to thaw naturally. That’s why the Forensic Team’s estimate of the time of death was off. The killer took advantage of the thawing period to create an Alibi. I have to say, this method not only returned the body to the Primary Crime Scene, but also provided a solid Alibi and misled our Forensic Team about the time of death-three birds with one stone! But even the most meticulous plan has its flaws. The killer never expected that there would be continuous scorching weather after the murder, which left us with the most crucial clue: the blood traces!”

As soon as Wen Sibao finished speaking, the fax machine on his desk began to clatter. Moments later, a test report from the Provincial Forensic Team was faxed over. After glancing at it, a confident smile appeared on his face, and he handed the faxed report to Li Mengxue.

Li Mengxue took the Provincial Forensic Team’s test report and saw at the top: “According to the corpse sample sent by the Mobei Criminal Investigation Division’s Forensic Team, multiple ruptured cell injuries were found in the sample. Conclusion: The body was subjected to freezing treatment after death.”

Li Mengxue asked in astonishment, “Isn’t this the Provincial Forensic Team’s test report? Senior, when did you send the corpse sample over?”

Wen Sibao replied, “Actually, after seeing your Forensic Team’s results, I suspected the killer might have tampered with the body somehow, so I took the liberty of sending a sample to the Provincial Forensic Team for testing. As I expected, the killer used freezing, which caused your team’s estimate of the time of death to be inaccurate. But this method has a drawback: ice has a larger volume than water, so the cells inside the body show ruptured injuries during testing.”
Xu Wudi, who had been silent all this time, finally couldn’t sit still. He muttered quietly, “You… still don’t trust Master Mengxue after all!”

On the other hand, Li Mengxue showed no sign of dissatisfaction toward Wen Sibao. Instead, as she looked at him, her eyes were filled with even more admiration.

Wen Sibao paused, then continued his analysis: “Given that the suspect had a direct financial dispute with the victim, our police would quickly suspect him. Therefore, the suspect needed to entrust a third party unconnected to the victim, namely his accomplice, to bring the body back to the crime scene. The reason the killer didn’t dispose of the body elsewhere is that, during this period, whether leaving the city or entering any public place, the trunk is the first place security personnel check. Rather than risk dumping the body somewhere, he would rather create a solid alibi to completely clear himself of suspicion. That way, no matter how we investigate, we won’t trace it back to him.”

Wen Sibao stood up, explaining excitedly, “Now we know the body was frozen, and the cold storage facilities in Mobei City are concentrated in the southern district. So we need to check two things: First, Mengxue, you’re responsible for re-examining the surface of the body’s skin to see if there are any remaining linen fibers from the sack. Second, I’ll check the surveillance footage of vehicles from two to three hours before the crime and compare them with the vehicles seen by cameras around the crime scene. If there’s a match, that’s most likely the vehicle used by the accomplice!”

Seeing Wen Sibao’s confident demeanor, Li Mengxue felt as if a little rabbit were hopping in her chest. After a moment, she unconsciously blurted out, “Senior, you…”

Before Li Mengxue could finish her sentence, the office door was suddenly pushed open, and Murong Shui’s playful greeting rang out.

“Hello! Wen Baobao (playful nickname)! Mengxue (little sister)! Your grandaunt (playfully) is here to see you!”

Hearing Murong Shui’s greeting, everyone turned to look and saw Xu Tiannan standing beside her. Instantly, complicated expressions appeared on their faces.

The last time Xu Tiannan met these people was when he was invited to assist the Criminal Investigation Division in solving the 4.15 serial theft case. Although he was there to help, the first thing he did was help the only suspect clear his name.

That case was quite simple. The trace inspection team collected an unusually clear bloody handprint at the crime scene and found an unconscious man in a vegetable cellar two hundred meters away. Investigation revealed that this man had three prior convictions for theft, and his fingerprints matched those in the bloody handprint at the scene, so he was quickly convicted.

However, the strange part of the case was that the suspect insisted he had been knocked out and dumped in the cellar that night, refusing to admit to the assault and theft.

Xu Tiannan’s method for clearing the suspect was simple. He had the leader of the Criminal Investigation Division coat his hands with a red ink pad and, in front of everyone, press his palm against a white wall. After the palm print appeared, something unexpected happened: the thumb left only half a fingerprint. The leader tried again on another part of the wall, and once more, only half a thumbprint was left.

This experiment revealed the problem: the handprint found at the crime scene was a clear palm print showing all five fingers.

Xu Tiannan explained: Due to the physiological structure of the human hand, when the whole palm is pressed against a wall, only half a thumbprint will be left. Therefore, the clear palm print showing all five fingers at the scene could only have been made if the suspect, while unconscious, had his fingers pressed one by one onto the wall by the real culprit.

Later, Xu Tiannan analyzed the behavioral patterns of the suspect’s gang and ultimately helped the police solve the theft case and find the real culprit. However, even though the case was solved, the leader of the Criminal Investigation Division was embarrassed for having arrested the wrong suspect. He even called Wen Sibao into the office for a thorough scolding, ordering Wen Sibao never to let such an incident happen again.

But words are just words. When a real case comes up, they still need Xu Tiannan, the criminal investigation expert, for assistance. Besides, Wen Sibao knew that, in the future, he’d inevitably be caught in the middle, pleasing neither side.