Fang Ling's words made Mu Zihan a little ridiculous, and I also had a stomachache from laughing, but it seemed that Mu Zihan didn't dare to say to her in that mocking tone like he did to me, but said after stroking his forehead and smiling: "No, Fang Ling, if the rivet is loose, people will have a chance to get out." Pen Fun Pavilion www.biquge.info"

Then he carefully explained: "Maybe because you women are not very interested in this aspect, so you don't usually pay special attention to it." In fact, the fence at the top of this old fence-type anti-theft window is generally not as tightly arranged as the other faces. It may be due to the existence of iron sheets, so I think it doesn't matter if the rows are not so close, anyway, as long as the iron sheets can be supported and fixed. Therefore, if the rivet holding the iron sheet is partially loose, then if the iron sheet is lifted, there will be a hole on top of the burglar window that is enough for an adult to climb out. ”

"Of course, not all security windows are like this." Immediately afterwards, Mu Zihan added: "It's just that the anti-theft window in Inspector Chu Hengyu's study, I have checked and confirmed, and it is indeed the case." Moreover, the iron sheet in the upper right corner of it also has a corner of the rivet that has fallen off due to aging, and now it only relies on a few ropes to pass through the hole of the original rivet and tie it to the fence of the anti-theft window to fix the iron sheet. In addition, if you look closely, you will find that there are obvious traces of folding on the iron sheet, which is the best proof that someone once lifted it and went out from here. ”

"Oh." Fang Ling responded thoughtfully, it seemed that she still seemed to understand, but Mu Zihan had already made everything clear, and then she could only rely on herself to understand.

"Oh, I have one more question." After seeing them finish, I interjected at the right time. Although I have roughly figured out the modus operandi of the murderer in this case. However, there are still one or two points that I haven't figured out, which makes me feel like a fish in my throat, and I don't vomit unhappily: "I probably know this modus operandi, but there are still two points that I don't understand." ”

"Which two?" Mu Zihan asked.

"You just said that if you use this modus operandi, there is a high probability that the murderer will leave traces on his hands, but I can't infer what kind of marks will be. Rust? It's been more than a day, and it's been washed off a long time ago. I asked suspiciously, "Also, the windows of the study were locked from the inside at that time." Although the murderer can use this technique to pass through the burglar-proof window, how can he lock the window from the outside? ”

"Oh, this one." Mu Zihan smiled and said, "Siyuan, in fact, the two questions you asked can be answered with one answer. It is precisely because the murderer went out of the window at the scene of the crime, climbed onto the burglar-proof window, and then locked the window from the outside, that it is possible to leave marks on his hands. ”

Then, he explained to me in detail that the murderer used a little trick and gadgets when he locked the window of the study.

Like the lock of the aluminum alloy window in Chu Hengyu's study, it is the more common buckle lock. That is, in the middle of the left and right windows, there is a circular lock. As long as the lock is broken up, the windows on both sides cannot be opened, that is, they are locked.

"If a lock like this is originally locked, it will be more troublesome to open it from the outside. However, if it is left open at first, it is not difficult to lock it from the outside. Mu Zihan smiled and continued to explain: "With just a little tool, a fishing line of the right length can be easily completed. ”

Then, he gestured to explain to us, and I finally understood the murderer's modus operandi.

It turned out that after the murderer attacked Inspector Chu Hengyu, he first deliberately knocked down the bookcase, pretending to be an accident. Then take out the fishing line that has been prepared in the morning, tie one end to the handle of the window lock, and then put the middle of the fishing line through the top and bottom of the window, so that the other end of it is also outside the window.

Because the fishing line is very thin and has a certain toughness, it is easy to fit into the gap between the bottom edge of the old-fashioned aluminum alloy window.

After that, as long as the murderer climbs out of the window, closes the window, and then pulls the fishing line vigorously from the outside, he can pull up the small handle of the window lock little by little, and when it is straightened, the window will be locked naturally.

After the window is locked, he just needs to continue to pull the fishing line hard. Since the fishing line is relatively strong, it is not easy to break and has a smooth surface. The handle of the window lock is made of metal, and the surface is relatively smooth. Therefore, under continuous force, the fishing line tied to the lock handle will slowly slide upwards. In the end, he completely broke away from the handle and was pulled out of the window by the murderer from the top and bottom of the window.

In this way, the window looks as if it was locked in the first place, and the secret room at the scene of the crime is completed.

After that, the murderer only needs to untie the rope that holds the iron sheet and fence at the top of the anti-theft window, lift the iron sheet, and climb out through that opening to the top of the anti-theft window.

Tie the rope back and fix the sheet again. Then use the rope prepared in advance, using the method of the double-strand rope that I deduced earlier, and go downstairs.

Well, a closed room murder that looked like an accident was done.

Next, as long as the tools of the crime are destroyed, everything will seem to be seamless, and it will become an almost perfect impossible crime.

It's a pity that this murderer met Mu Zihan, and he cracked this complex and bold modus operandi from the little clues he left at the scene.

"And the reason why I speculate that there are marks on the murderer's hands is because the fishing line is actually very sharp. If you pull too hard, it is likely to cut the palm of your hand and leave a thin scar on it. Mu Zihan explained: "In addition, the reason why the iron sheet is not so compatible with the fence when it is fixed back, resulting in a crashing sound when it is blown by the morning breeze. Because, after all, the murderer was standing on top of the burglar-proof window at that time and tied up without any protective measures. Out of human self-protection, he must have used one hand to firmly grasp the fence of the burglar window to prevent himself from accidentally falling. Therefore, the rope can only be tied with the other hand and with the foot. As a result, the knot could not be tied too tightly, leaving the biggest loophole in the modus operandi. To put it bluntly, Skynet is magnificent and not leaky, as long as it is a case committed by a person, it will never be seamless. ”

"Of course, the reason why it can't be the first suspect is that even if the fence at the top of the anti-theft window is relatively sparse, according to my observation, there is only a square hole about 40cm in length and width." After Mu Zihan finished speaking, he added: "With the figure of the first suspect, it is impossible for him to get through such a small hole." ”

(To be continued)