The ring-shaped patterns slowly emerging from under the skin were reflected in his pupils as a distorted light.
This light was like a key, unlocking a long-sealed door deep within his mind.
Zhou Mingyuan's regenerated fingerprint was not an isolated case. There was some kind of resonance between it and the cufflink that he had yet to understand.
He immediately pulled up the cufflink's ion scan report, magnified the screen, and repeatedly compared it with the distribution map of the Technetium-99 element.
At first, he thought this radioactive residue would be evenly distributed like dust, but the reality was the exact opposite.
These trace elements showed a strange "memory deposition"—they were almost entirely concentrated in the area of the fine engravings on the inside of the brass cufflink.
The distribution pattern was highly irregular, as if some intense emotion had once "burned" fiercely inside the metal, branding its own traces at the atomic level.
This wasn't physical adhesion at all; it was more like... an inscription.
An idea struck Shen Mo. He retrieved the cufflink, sealed in its vacuum bag, from the evidence locker.
He put on anti-static gloves and carefully secured it on the microscope stage.
A micro-camera slowly advanced, probing deep into the fine cracks that had formed over the years on the inner wall.
Under normal light, everything was as usual, just the cold texture of metal.
But he didn't give up. He switched to the UV-enhanced mode.
The moment the mode switched, on the screen, from the deepest part of the cracks, a very faint yet incredibly clear network of blue fluorescent veins was captured.
The veins were as fine as spider silk, shaped like ripples spreading across a still lake after a stone is thrown in, and they were pulsating faintly at a frequency imperceptible to the naked eye.
It was still alive.
Shen Mo held his breath, an unprecedented shiver running up his spine.
He muttered to himself, his voice slightly hoarse from shock, "Not a curse... it's a 'field'." An energy field constructed from extreme obsession, capable of distorting the laws of physics.
The next morning, an urgent notification from the city bureau interrupted Shen Mo's thoughts.
A bizarre murder case had been discovered, located in a high-end apartment in the south of the city.
A woman living alone, Lin Wanqing, was found dead in her bedroom, her body lying stiffly on the bed.
The preliminary autopsy report from the forensic center was full of contradictions: the deceased's lungs were filled with fresh water, there was clear algae residue in her trachea, and even particles of typical riverbed sediment were detected under her fingernails.
All evidence pointed to drowning.
However, not a single drop of excess water could be found at the crime scene.
The doors and windows were intact, locked from the inside, with no signs of forced entry.
The humidifier in the bedroom was not on and was dry inside. Professional instruments determined that the air humidity in the entire room was only 42%, which was even considered dry for a coastal city.
The mainstream opinion within the police was that the victim was drowned elsewhere, and the murderer then used some clever method to move her back to the bedroom and fake a locked-room scene.
Shen Mo went to the scene himself for a secondary investigation.
Traces of the police investigation still lingered in the apartment. The air was filled with a mixed smell of aromatherapy and stuffiness.
He ignored the obvious clues and walked straight to the bed, crouching down to carefully examine the deceased's body.
Soon, on the outer side of the victim's smooth calf, he discovered several almost imperceptible parallel pressure marks.
These marks were extremely shallow, but their distribution was unusually regular. The variation in depth perfectly matched the pressure distribution characteristics that an object experiences at different water depths according to fluid statics.
What startled him more was that the wrinkles on the deceased's skin showed the "maceration" characteristic of being soaked in water for a long time. But when his fingertips touched it, there was only the unique coldness and dryness of a corpse, with no evidence of contact with water.
It was as if she had been drowned in an invisible body of water that existed only for her.
Shen Mo stood up and looked around the almost abnormally dry bedroom.
He took out a packet of highly absorbent blue silica gel powder from his investigation kit and, like sowing seeds, sprinkled it evenly on the floor, especially in the area between the bed and the door.
Under the puzzled gazes of his colleagues, he waited quietly.
One minute, two minutes... just as everyone thought it was a futile effort, a change occurred.
In an area of the evenly spread blue powder near the foot of the bed, the outline of a blurry but complete footprint slowly appeared at the edges.
The moisture absorption reaction of that outline was stronger than the surrounding area, its color becoming deeper. The shape was complete, the direction clear, extending from the bedside towards the door.
It was as if, not long ago, a soaking wet person had walked through here, treading on a floor of "invisible water."
Shen Mo immediately requested all of Lin Wanqing's social media records and communication information from before her death.
In the vast amount of data, one clue caught his attention: the deceased's best friend, Zhao Wan, had, in the past year, advised her at least five times in WeChat chats to "stop going to that river, it's too dangerous."
An hour later, in the city bureau's interrogation room, Zhao Wan appeared nervous and sad.
At first, she was vague in all her answers to the police, insisting that Lin Wanqing just occasionally liked to go to the river to relax and that there was nothing unusual.
Shen Mo didn't argue with her. He just pushed a copy of the deceased's diary in front of her.
On the paper, in Lin Wanqing's elegant handwriting, were the words: "I dreamed he sank again. The water was so cold. I still couldn't grab him this time."
Seeing these words, Zhao Wan's psychological defenses instantly collapsed.
She covered her face and finally confessed everything.
Lin Wanqing's college boyfriend, Chen Hao, had, ten years ago, due to fierce opposition from both their families, jumped from the bridge over the Old Town River on a stormy night and never came back up.
From then on, Lin Wanqing changed.
Every year, on a rainy night, she would go to the riverbank alone, sit where Chen Hao had jumped, and stay until dawn.
Last summer, on another stormy night, Lin Wanqing accidentally fished a broken stone tablet, washed by the current, out of the shallows by the river.
The material of the tablet was very old, and two words were vaguely carved on it: "Lin · Chen."
She felt it was a response from Chen Hao, so she secretly brought the broken tablet home and hid it in a secret compartment of her bedroom dresser.
"After that, she started saying strange things," Zhao Wan sobbed, her voice trembling. "She said, one time she was holding that stone to sleep, and when she woke up in the middle of the night, she felt the river water suddenly turn warm, like... like he was holding her."
Shen Mo immediately drove with Su Wanying to the Old Town River, the site of the tragedy.
The river water was murky and slow, the banks showing signs of years of erosion.
Su Wanying carefully collected moss samples from the crevices of the riverbank stones to compare with the algae in the deceased's lungs.
Just then, an old fisherman in a black-canopied boat silently rowed towards the bank.
He seemed to recognize the police uniform on Shen Mo, hesitated for a moment, and then handed over a yellowed photo wrapped in a plastic bag.
The photo was taken in the 1970s, during a river dredging project.
In the center of the photo was a complete stone tablet, the inscription clearly visible: "For life or for death, however separated, to our wives we pledged our word." The signature was "From Chen XX to Lin XX."
"This is when the tablet wasn't broken," the old fisherman, Old Wu, said in a low voice. "My grandpa said this tablet was erected by a pair of lovers from long ago. Later, there was a big flood one year, and the tablet was broken by the floodwaters, split into several pieces. After that, there were always rumors around here that you could hear someone crying in the river at night, like they were piecing the stones together, piece by piece."
Shen Mo's heart sank. He immediately used his phone to pull up the city's meteorological data for the past ten years.
A startling coincidence emerged: on the night Lin Wanqing was found dead, around midnight, the air humidity in the Old Town River area had experienced an abnormal surge, with a peak value of 98%. This data was almost identical to the humidity record from the stormy night ten years ago when Chen Hao had thrown himself into the river.
He took out his portable infrared thermal imager and scanned the area where Old Wu indicated the stone tablet might be buried.
On the screen, amidst a normal expanse of blue cold light, there was an irregular, abnormal thermal gradient beneath a certain part of the riverbed.
The heat was not intense, but it was stable, as if there was a "memory heat source" underground, being quietly activated in some unknown cycle.
Back at the forensic center's lab, Su Wanying had already reached a conclusion: the diatoms isolated from Lin Wanqing's lungs had a genetic sequence that perfectly matched the samples collected from the crevices of the Old Town River stones.
The mystery was being unraveled, layer by layer.
Shen Mo immediately designed a bold simulation experiment.
He placed the fragment of the stone tablet found in Lin Wanqing's bedroom into a large, sealed environmental chamber. Then, he had the technicians precisely control the humidity inside the chamber to 98% and began to loop the authentic audio of the thunderstorm from that stormy night ten years ago, as recorded by the city's meteorological station.
Time passed, minute by minute.
Three hours later, an incredible scene occurred.
The air inside the originally transparent chamber began to condense into a visible thick fog. On the metal floor of the chamber, a small amount of water actually appeared.
Upon testing, the composition of this water was highly consistent with the water from the Old Town River.
Su Wanying put on protective goggles and carefully approached the stone tablet inside the observation chamber. Suddenly, she let out a short gasp. "Captain Shen, look at the tablet's surface!"
Shen Mo looked up and saw that on the fragment of the stone tablet, the originally blurry carved words "Lin · Chen" were slowly, drop by drop, seeping a dark red liquid, like newly opened wounds.
The liquid was neither blood nor rust, yet in the sealed air, it emitted a faint, fishy smell unique to the Old Town River.
Shen Mo's gaze did not linger on the stone tablet, but was fixed on the steadily rising and then stabilizing temperature and humidity curve on the monitor screen.
He picked up a pen and, on a blank report sheet, slowly wrote the first sentence of his conclusion for this case:
"The echo is not a simple replay of the past... it is replicating a 'reality constructed by obsession'."
He put down the pen, looking at the words, his eyes deep.
He knew that every word of the report he was about to submit would be a challenge to the existing cognitive system.
This report itself was the beginning of a storm.
(End of Chapter)