July 5, 9:40 a.m., Metropolitan Police Department.

"Huh?" When Chiba and Ash Hara are led by a police officer to a room with a CCTV turned on, they see Conan and Moriran who are just as surprised as they are. "Why are you here?"

"Mr. Maori brought them here," the officer had already given an answer before Conan could reply. "It seems that it was because the Matsumoto manager heard that Conan's children have very keen observational powers, so he asked Mr. Mori to bring him with him - Miss Mori Ran is here to take care of Conan."

"Were you also called by Matsumoto Administrator?" Conan asked Chiba.

"Forehead...... "Qianyu raised his eyebrows." I think...... Probably not because of this - Gray Yuan and I found a missing part of a body at Dr. Asasa's house yesterday...... Wait a minute, didn't Dr. Asasa tell you? ”

"Limbs?" Conan was stunned. "I was watching the World Cup last night (July '94 was the World Cup in the United States, Conan watched Ireland 0:2 Netherlands and USA 0:1 Brazil in the round of 16), so I was at home all the time and didn't get a chance to meet with the doctor. Then I was pulled over directly by my uncle this morning. Anyway, the meeting will be about it later, right? ”

"I don't think so," Chiba shook her head. "Today could be something else."

"Do you know the inside story?" Conan asked hurriedly. "Tell me?"

"You'll find out later," Qian Yu said. "Why should I spoil it?"

…… At 10:05 a.m., the CCTV footage of the meeting started on time. Kogoro Mori and Officer Shiratori sat in chairs in front of a blackboard with several photographs posted, while on the other side of the room, Executive Officer Matsumoto and Officer Twilight sat in front of a blank drawing board. In front of them, police officers from all over the country sat in pairs at wooden tables, ready to listen to their reports.

"The case we are discussing today is a serial case codenamed 'Avid Gambler,'" Officer Shiratori picked up his notebook and stood up. "In addition to the five cases that we have already reported to each other before, there was a car accident on the highway in Odawara yesterday, and our police officers found a mahjong tile at the scene of the accident in the same place as the previous five cases, so it can be concluded that this car accident is also part of a serial case. However, considering that the modus operandi of the sixth case is quite special, and the investigation has not yet been completed due to time constraints, we will discuss the first five cases first. ”

"First of all, except for the sixth case, the other five cases have a common way of committing crimes, according to the investigation, they should all be knocked unconscious by a stun gun, taken to the place where the body was found, and then stabbed the deceased in the back with a large knife in his right hand. The main question that arises about this is why the murderer had to use a stun gun to knock the unconscious victim unconscious and then move the unconscious victim to the place where the body was dumped, and then commit the murder? In addition, the pictures of the mahjong tiles in these six cases are on the blackboard behind me - six seven-pie tiles painted red in different circles, separated by a vertical line on the back, and the six symbols A, E, A, and the inverted L, H, and Z are written on them, the meaning of which is currently unknown. ”

"In addition, after identification, these deceased people have all been lost and only one thing they usually carry, which is mentioned in the information paper we sent to all of you, please read it."

Of course, it was impossible for Chiba to provide these materials to them, but Chiba managed to learn about them - he saw the missing items of each of the six victims through footage collected from the blackboard on CCTV - necklace pendants, wallets, protective bags, motorcycle key rings, vanity cases, and mascot dolls.

From a statistical point of view, if all people lose and only lose the same thing that they always carry on their bodies, the probability that this phenomenon is a random result of non-human is very small, and it is very likely that the murderer did it intentionally. But the question is, for what purpose did the murderer take these things?

Just then, the door to the room opened, and Grigory walked in.

"Do you see this?" Grigory said after glancing at the TV. "There's nothing nutritious in the back anymore, Qianyu, you and your girlfriend come out, and Matsumoto is looking for you."

"Steward?" Chiba was stunned and looked at Kiyocho Matsumoto, who was still sitting on the CCTV.

"This CCTV has been delayed for a long time, and now the Administrator has come out," Gregor tapped the ground with his cane. "Come with me, don't keep the stewards waiting too long."

……

Managing Officer Matsumoto didn't ask Chiba and Ash Hara too many questions, but only asked them to recall the scene at the time, and then gave them a detailed summary of the two sets of serial murders, and vaguely expressed the hope that they could look for clues hidden in them, and once found, contact him directly through his mobile phone.

But as they walked out of the transcription room together, they encountered something very interesting.

"Matsumoto Police!" Mao Liran, who was originally standing in front of the drink machine and buying drinks with Conan, saw Matsumoto Kiyocho and Chiba walking out together, and hurriedly greeted Matsumoto Kiyocho. "It's been a long time, is Sayuri-sensei's health okay?"

"Are you ......" Matsumoto Kiyocho's face flashed with a hint of confusion before revealing a look of sudden realization. Oh, you're from a Maori family...... Sayuri is still the same, that's all. ”

At this moment, the singing sound of a voice that was very unsuitable for singing reached their ears.

"O crow—why sing? Because on that high mountain? A police officer with a funny face walked up to them while singing the nursery rhyme called "Seven Crows."

To be honest, although his voice is not suitable for singing, singing this funny song has a different sense of matching.

But in the place that Qianyu's gaze did not cover, someone's face changed instantly.

"Officer Yamamura, where did you hear that song?" Conan ran up to the officer and asked.

"Huh?" The man known as the mountain village was visibly upset, and then he flipped through the documents that were half in his chest pocket and showed the data page to Conan. "You may not know, but I've been—"

As he spoke, he tapped the words "Police Department" prominently on the information page.

"Mountain Village Police Department, why are you singing this song?" The corners of Conan's mouth twitched, and then he changed his name to the mountain village again.

"Because when I was in the bathroom just now, I heard a keyboard dialing sound that looks like this song," Yamamura explained. "It's almost exactly the same button sound as 'Seven Crows.'"