Eight-Hundred-Year-Old Technique

Lin Xinyi's second method was very simple.

He wanted the hundred-plus passengers at the scene to cooperate with him, leave the underground platform together, return to the surface, walk out of the tram station, and finally line up on the sidewalk.

That was the entirety of his request to those passengers.

The passengers present were all utterly confused by this:

They could not find the murderer on the underground platform, so how would standing by the roadside after going aboveground help them find one?

Was the murderer made of ice cream, ready to melt under the sun?

"What a load of nonsense."

No one understood this method.

But since they had promised Lin Xinyi that they would cooperate with his investigation as much as possible, and Lin Xinyi had promised to let them go immediately if he could not find the murderer within ten minutes, the passengers reluctantly agreed in the end.

Thus, under the organization of the tram station staff, the hundred-plus passengers formed a loose, disorderly line and filed grandly out of the underground platform, back up to the surface.

Throughout the entire process, Mouri Ran stood nearby to keep watch.

She kept a fierce eye on the passengers the whole time, preventing any of them from slipping away halfway through.

And so—

Without incident, all hundred-plus people were moved aboveground.

Lin Xinyi led them out of the tram station and onto the sidewalk outside.

At Lin Xinyi's request, the hundred-plus passengers noisily divided into three crooked rows, keeping some distance from one another as they stood parallel along the sidewalk.

Looking at the scene—

Anyone unaware of the situation might have thought they had come here to do morning exercises.

"What exactly are we doing?"

"It's so hot. Can this really find the murderer?"

Standing on the sidewalk under the blazing sun, some passengers had already begun to complain.

Indeed, the inside and outside of the tram station were practically two different worlds.

The tram station had air conditioning, and the environment was cool and comfortable.

Outside the station, the sun scorched their faces, the air was filled with searing waves of heat, and annoying flies and mosquitoes buzzed endlessly around their ears.

They had only been standing there for less than half a minute, yet many people were already drenched in sweat.

"Mr. Lin, how exactly are you planning to investigate?"

Someone asked in confusion.

"Just stand there." Lin Xinyi gave a perfunctory reply.

At the same time, like an instructor supervising students during military training, he carefully paced back and forth before the three rows of passengers, inspecting them from one end to the other, then back again.

"He isn't using any special methods. He's just looking at them over and over..."

"What is Mr. Lin Xinyi trying to do?"

Suzuki Sonoko muttered beside him in confusion.

"This..." Kudo Shinichi hesitated for a moment, unable to make sense of it either.

In his eyes, what Lin Xinyi was doing now was probably similar to what detectives did.

That was, using every clue from a person's clothing, manner of speech, gaze, movements, walking posture, and microexpressions, along with imagination and logical deduction, to infer their identity, background, profession, and experiences.

Just as Sherlock Holmes could tell at first glance that Watson was an army doctor returning from Afghanistan, great detectives were all skilled at this technique of "reading a person on sight."

But Kudo Shinichi knew very well that reading a person on sight required not only formidable intellect and keen observation, but also did not work every time.

For it to work, the observed person had to happen to have enough clues available for observation.

But there were more than a hundred people here.

To observe over a hundred passengers within just ten minutes, while also picking out a murderer deliberately hiding himself among them, was simply a fantasy.

Could he really do it?

Or was he observing not the passengers themselves, but something else?

Kudo Shinichi vaguely guessed something.

Just then, Lin Xinyi finally began to speak.

"You must all be wondering why I brought everyone outside the tram station, right?"

He stopped in front of the passengers, meeting each pair of questioning eyes with his own.

"The reason is actually very simple."

"Because there is something outside the tram station that can help me find the murderer."

"And there is almost none of it on the underground platform."

"What is it?"

The crowd looked at one another and asked in confusion.

"No rush. Speaking of this..."

"Let me first tell everyone a short story."

Unexpectedly, Lin Xinyi did not reveal the answer directly. Instead, he began telling a story.

"In 1247 AD, the seventh year of the Chunyou era under Emperor Lizong of the Southern Song Dynasty, the forensic scientist Song Ci, then serving as Hunan Provincial Judicial Commissioner, compiled the forensic materials he had collected and summarized throughout his life into a book. He wrote the world's first systematic work on Forensic Medicine, Collected Cases of Injustice Rectified."

"The publication of Collected Cases of Injustice Rectified marked the birth of Forensic Medicine in the systematic sense."

"..."

Everyone present was bewildered.

Why was he talking about history while investigating a case?

And he had started directly from the beginning of Forensic Medicine—

Why not start from the birth of Amenominakanushi-no-Kami?

Lin Xinyi ignored their doubtful looks and merely continued his story.

Moreover, his tone carried reverence.

Just as Kudo Shinichi admired Arthur Conan Doyle, the "father of detective fiction," Lin Xinyi, as a forensic scientist, had always held the highest respect for Song Ci, the universally recognized "father of Forensic Medicine."

And now, he was going to solve the case using the method passed down by his forefather.

"In Collected Cases of Injustice Rectified, written by Song Ci, there is such a case recorded."

"One day, a corpse was found beside a road in a village. The victim's clothes and belongings were still present, and there were more than ten sickle wounds all over the body."

"The local investigator in charge of the case initially determined that the victim had been killed out of personal vengeance. He then ordered the villagers to bring out the sickles from their homes and place them together under the sun."

"Just like now, it was midsummer at the time, and many flies were buzzing around the scene."

"But before long, the flies lingering at the scene inexplicably gathered together. Out of the seventy or eighty sickles at the scene, they 'chose' one and continuously swarmed around it."

"So the investigator found the owner of that sickle and said to him—"

Lin Xinyi paused slightly before calmly reciting the original words from Collected Cases of Injustice Rectified.

"'No flies gather on the sickles of others. Yet you killed a man, and the bloody stench remains. The flies have gathered here. How can you hide it?'"

"Those watching around them gasped in admiration, while the murderer knelt and confessed."

He quickly finished telling the ancient story.

The expressions of the crowd changed slightly, as if they had all vaguely thought of something.

"This was the earliest case of solving a crime through Forensic Entomology."

"The reason flies could help the investigator find the murderer was because their sensory systems are extremely sensitive—even trace amounts of blood that have been washed away and are invisible to the naked eye can easily be detected by them."

"And blood, rich in nutrients, happens to be one of flies' favorite foods. As long as they smell blood, these little creatures cannot resist gathering wherever it is present."

Lin Xinyi slowly explained the principle behind using flies to find a murderer, his gaze gradually turning sharp.

"So, do you understand why I brought everyone out of the tram station?"

"Because the temperature inside the tram station is low, and there are few flies."

"But outside the tram station, the temperature is high, and there are many flies."

As he spoke, he paused, his eyes locking firmly onto a certain man in the crowd.

"This case is just like the story mentioned in Collected Cases of Injustice Rectified. The murderer killed someone, and once he killed someone, blood would have gotten on his hands."

"And bloodstained villains are the favorite companions of flies."

The moment he finished speaking, everyone followed Lin Xinyi's gaze and turned their eyes toward that man.

The man had a gentle-looking face and wore clean clothes. There were no visible bloodstains on him, nor did he possess any so-called murderous aura.

No matter how they looked at him, he was merely an ordinary, mild-mannered person.

But at this very moment, around this "ordinary person"—

Flies drawn by the smell were swarming everywhere.

"Come out, Mr. Murderer."

Lin Xinyi looked at the man with unwavering eyes.

"You have already been defeated by an Eight-Hundred-Year-Old Technique."