Qin Ming and I glanced at each other, and it seemed that there wasn't much news we could hear from the security guards. Before we could speak, the security guard sighed slightly and said, "By the way, I did think about it, a few times, I saw that long-haired young man at the door, and he seemed to like that girl very much." On the night before her accident, he walked to the door and waited until the girl had entered the door before leaving. Later, I heard that he was also called over for questioning, right? ”

"Are you sure? Didn't it rain the night before? How did you see that lad? Curious, I pressed on, and Matsuko did say that it had rained overnight the night and had not stopped the next morning.

The security guard laughed: "He's so easy to recognize, tall and thin, so fair, and with long hair, he suddenly looks like a girl." He seemed to be ...... that day It's a flower umbrella. You can tell at a glance that it's him......"

I nodded. The security guard shook his head and said, "It's a very infatuated young man, and then ...... When the girl's family moved the things here, he also asked the people to take the books with them, saying that it was a thought anyway, and it was also the most important thing for the girl on a daily basis. But no one in the family paid any attention. It's no wonder that he looks like a Chinese, but all he says is in foreign language, as if he is really a devil...... The most pitiful thing is the young man. By the way, if you can get the key here, it means you've already met the young man, right? Is he still going to continue to pay rent for that house? Otherwise, we may continue to rent the house to others when the time comes. ”

"He'll be coming soon, will he continue to rent. It's up to him to make his own arrangements. But until then, I hope this house is still there, and maybe there are any clues to the investigation in it. I nodded and continued.

The security guard nodded, "Okay." I think he'll probably leave. No matter how much you like that girl, it's important to live your life first. When I saw him last year, he seemed to be a little better than the year before. However, if it were me, I would have been impressed. Unlike the group of people who seemed to like that girl before, after that girl's accident, all of them disappeared......"

"There are other boys? Have you seen them all? I asked curiously.

The security guard nodded: "Don't you know?" The girl moved here. It's just to avoid the harassment of those people. There used to be people singing downstairs, but they were chased away by the merchants. There are also people who have come here to deliver flowers, chocolates, etc., but they have also been sent away by us. Otherwise, who would want to spend so much money to rent a house here? Even if the girl's family has money. It's not such a waste, is it? ”

"Have you seen this man?" I pulled out my phone. That was when Qin Ming called up Sun Changqing's husband and wife files. I picked out the photos from it.

The security guard looked at it seriously for a while before saying, "Yes, yes." He's been here a few times, but every time he's been here it's daylight, right? I heard that it was a teacher at that school. Every time I come here though. Left shortly after. Looks like a very decent person. ”

We got more useful information from the mouths of the security guards, and this was later confirmed again from the mouths of Songzi and Zhao Yan. The teacher who managed the piano room back then also said the same thing: although the situation was a little chaotic at that time, the order would not be wrong, she and Zhao Yan were too concerned about the situation inside, so they looked in through the glass, but they didn't expect the door to open, but they couldn't open it, and then they saw Casey on the sofa. In a panic, they screamed, and Matsuko appeared. After about 20 minutes, the caretaker and the security guard came running with the key, only to find that the burglar chain in the room was hanging from the inside, and they had to go and find a large pair of pliers to cut the chain before they could open the door.

"That's where the biggest problem lies." Qin Ming's brows furrowed, "This is a secret room, if this problem can't be solved, then there is no way to continue the investigation." Survey ...... three years ago It does seem a bit too hasty. ”

This is Qin Ming's first judgment on the case three years ago. Leng Ao looked at him seriously for a long time, "Since this is the case, then solve this puzzle and then make a judgment." Fang Qing, what do you think? Why haven't you heard anything say anything yet? ”

"What is there to say, why not just continue our investigation right away?" I frowned, "Judging by the content of the video, it is definitely not suicide. At the very least, I think the footage is problematic. If it is based on the above judgment, then the conclusion that Casey committed suicide is not valid. If you solve the problem of the secret room, you may be able to guess the key to the problem. ”

Qin Ming looked at me with wide eyes, "If you can open the door with just a key, maybe the problem is not so difficult, but the key to the problem is that there is a chain inside." After the murderer killed someone, how did he do it? It seems easy, but in reality, it's not that simple. ”

It's just that the theory is completely useless, so we can only go back to the scene of the crime again, and the chain that was cut has long been replaced. Although it is said to be a chain, it is a "V" line hook chain, and it is also a common anti-theft chain in some hotels. The key to solving the problem lies in how the other party locks the door and leaves. The possibility of coming in through the window has been ruled out, because it is the third floor, and the downstairs is a business, so the rooms on the second and third floors are equipped with anti-theft windows.

Thankfully, Leng Ao is here this time, so we can experiment again and again, and Qin Ming has also proposed countless possibilities. Because the purpose of that "V" steel is to prevent theft, an adult's hand can't be stuffed into it anyway. So, either way, you have to use tools to hang that "V" shaped chain.

If we use tools to design such a secret room, it is not difficult for us, there are many simple and easy ways to operate, even ordinary people can figure out how to design a secret room. Then, it can be deduced that the murderer has two possibilities: he has been planning to kill for a long time, so he will carry tools with him, so that a secret room can be arranged; But what if it is the second possibility, the murderer killed on impulse? He doesn't necessarily have tools with him, does he? (To be continued......)