Traveling back thirty years to Conan, intercepting Princess Eri

"The possibility is very high."

Hattori Heizo nodded and handed the documents to Hayashi Hideichi.

"During the subsequent police investigation, all staff members who worked at the museum that day, as well as the last group of visitors, underwent a thorough search, including their personal belongings, vehicles, and even the trash cans and sewers around the museum. Nothing was found."

"Moreover, the katana is over 1.2 meters long and the scabbard is inlaid with gemstones. It would be almost impossible to take it out of the heavily guarded museum without attracting attention."

"But the samurai sword is indeed no longer in the museum."

Konoe Taisho scratched his head, leaned closer to Hayashi Hideaki, and looked at the photos of the scene in the documents.

"The police searched the museum for half a month, looking inside and out. They examined the exhibition halls, warehouses, offices, and even the wall crevices, ceilings, and under the floors with instruments, but they found not a single trace of a knife."

"If it wasn't taken out, where could the knife be hidden? It couldn't have just vanished into thin air, could it?"

Lin Xiuyi didn't speak, but carefully flipped through the documents.

The crime scene in the photo was very clean. The glass of the display case had been pried open with an irregular gap, and no fingerprints or footprints were left around it.

On the deep red velvet cloth lining the display case, there is only a clear knife-shaped mark, proving that a samurai sword was once displayed here.

The materials also included a floor plan of the museum. The Warring States period artifacts exhibition hall is located on the east side of the second floor, surrounded by other exhibition halls and staff offices. The nearest exit is more than 50 meters away.

"Could it be that the thief had an accomplice in the museum and hid the knife in a place known only to insiders?"

Kawada Haeko crossed her arms and offered her guess.
"For example, staff lockers, or an abandoned warehouse, the police may not have found it."

"The police searched all the staff's lockers and personal belongings, leaving no corner of the warehouse unchecked."

Maeda Yoto's tone was certain.

“I saw in the documents that the police officer in charge of the case at the time specifically asked the museum’s long-time employees to confirm that there were no undocumented secret spaces.”

"Moreover, the museum was closed for a month after the incident, and the police searched the museum almost from top to bottom. If the samurai sword was really hidden in the museum, it would be impossible not to find it."

Kogoro Mouri squatted on the ground, staring at the cracks in the stone wall of the museum for a long time, then suddenly slapped his thigh.
"I know! Could it be that the thief threw the knife out the window? For example, before the police sealed it off, he secretly threw the knife into a hidden corner outside the museum and came back to retrieve it after things calmed down!"

“Impossible,” Hattori Heizo immediately retorted. “It was raining on the day of the incident, and the ground around the museum was wet. If someone threw something, they would definitely leave traces.”

"Furthermore, the police searched an area within a kilometer of the museum, including the green belt, parking lot, and even the nearby river, but found no trace of the samurai sword."

Everyone fell silent, with only the rustling of leaves in the wind filling the air.

Lin Xiuyi walked to the museum entrance, looked down at the floor tiles, and suddenly pointed to a location on the floor plan, asking,
"Where do the ventilation ducts in this Warring States exhibition hall lead? The information doesn't seem to provide details."

Hattori Heizo leaned closer and took a look, his eyes lighting up instantly: "I hadn't noticed that! The floor plan only shows the entrance to the ventilation duct, not the exit."

"I remember the museum's ventilation system was independent, with ventilation ducts in each exhibition hall connected to exhaust fans on the roof. Could it be..."

"Could the thief have hidden the samurai sword in the ventilation duct?"

Yoko Ono added quietly, this being the first time she had actively participated in the discussion that evening. Her voice was soft but carried a certain certainty. “For example, disassembling the knife into parts and hiding them in a concealed place in the ventilation duct. After the police search is over, we can come back and reassemble it when no one is around and take it away.”

Lin Xiu nodded, a glint of light flashing in her eyes.
"This is the most reasonable speculation at present. The ventilation ducts are narrow and covered in dust, so the police may have only checked the area near the entrance during the search and did not go deep into the ducts."

“Especially the exhaust fan on the top floor, which is usually overlooked, could easily become a hiding place for a knife.”

"But the katana is forged from a single piece and cannot be disassembled."

Konoe Taisuke squatted on the ground, clutching the documents, his chubby fingers tracing the samurai sword image on the photograph.
"Look at the connection between the blade and the hilt. They were forged together during the forging process and cannot be separated at all."

"Moreover, I checked the specifications of the ventilation duct beforehand. The largest diameter at the bend is only 35 centimeters. Even a 1.2-meter blade placed at an angle can't fit in there, let alone with a sheath."

"That's a contradiction."

Hattori Heizo leaned against the cold stone wall of the museum, his fingers unconsciously tapping the surface.

"It wasn't taken out of the museum, and it can't be hidden inside either. Could it be that this knife really grew wings and flew away?"

Kogoro Mouri squatted on the ground, drawing a simple floor plan of the museum in the dirt with a twig, muttering to himself.
"The entrance was sealed off, the ventilation openings were too small, the pipes couldn't be plugged in, and there was no secret passage... This case is practically impossible to commit."

At this point, he suddenly slapped his thigh, looked up, and said,

"Could the culprit be the curator?"

Kogoro Mouri's eyes gleamed with the light of a "famous detective."

"The fact that he was able to react so quickly after discovering the katana was stolen might be because he was the one who stole it, and he was prepared all along!"

"The police searched the curator's office three times."

Commander Konoe immediately retorted, pulling out an interrogation record from the pile of documents.
"There was a safe in the curator's office. The police broke it open and checked it. They even knocked on the wall behind the bookshelf to make sure there were no hidden compartments."

"Moreover, the curator was in a museum affairs meeting all afternoon that day, and colleagues can testify that he did not go to the exhibition hall at all."

"In addition, the curator's grandfather was the founder of the museum, and he himself worked at the museum for thirty years. He has a deeper affection for the cultural relics than for his own children, so he had no motive to steal them."

"If those police officers were truly capable, there wouldn't be so much crime in society."

Kawada Haeko pursed her lips, clearly not believing the police's findings.
"I still think the possibility of an inside job is the greatest! Raise your right hand if you agree, raise your left hand if you disagree, and we'll vote!"

As she spoke, she raised her right hand first, her arm straight as if afraid that others wouldn't see it.

"Hey, when did we start using a show of hands to decide prisoners? That's so unprofessional!"

Commander Konoe shook his head helplessly, but still raised his left hand.

"I believe the police investigation suggests that the possibility of an inside job is unlikely." (End of Chapter)