"It shows that Duan Feiyu is willing to drink the drink mixed with antifreeze." Fang Yuan followed Dai Xu's prompt and replied very naturally, after finishing speaking, he was also stunned for a moment, and immediately realized the connection between this and Ke Xiaowen, "Ke Xiaowen has no traces of struggling and fighting, so if the murderer can let Duan Feiyu drink a drink mixed with antifreeze, then maybe there is some excuse to fool Ke Xiaowen into agreeing to voluntarily accept the injection of hydrogen peroxide!" Just as it was impossible for Duan Feiyu and Wan Qian to know that what they ate was adulterated with toxic substances, Ke Xiaowen definitely didn't know what was in the syringe, otherwise no matter how cowardly a person was, he would always have some survival instincts. Then in this way, the problem comes, those things that eat and drink are better to say, Ke Xiaowen is an injection, this is not easy to be fooled than giving some food and drink, why did he choose to believe it? What reason did the murderer use to deceive him? ”

"You know, when a person, from the bottom of his heart, has a very urgent pursuit of a certain result, this person often becomes very blind and gullible, which is the same as the so-called emergency medical treatment." "So the key to convincing them is to know what they are desperately pursuing, and if you grasp that, you can grasp their weaknesses." ”

After hearing this, Tonic nodded: "It's a grade." ”

Fang Yuan suddenly realized that the murderer chose them and was able to succeed, in the final analysis, the crux of the problem was the common weakness of Ke Xiaowen and Duan Feiyu - the desire to improve their grades.

"After lunch. We'll have to continue to divide the work, while it's still during the day, and it's still during business hours. Supermarkets and sporting goods stores that sell target brand dumbbells and foot-tied sandbags still need to continue to investigate, and the surveillance footage collected before also needs to be carefully reviewed by several people. Dai Xu looked at the time and said.

Tang Li immediately volunteered: "I'll take a few people to sift through the surveillance video." ”

Dai Xu nodded, and had no objection to this: "Then Fang Yuan and I will continue to check the supermarket." ”

Although there were still Wan Qian's mobile phone and computer chat records at hand that needed to be screened, there was no problem with those things being done at night, but the business hours of shops and supermarkets were fixed, and they didn't wait for anyone, so Fang Yuan didn't raise any objections. Nodding, he and Dai Xu hurried to finish their lunch and set off separately.

Spend the afternoon in various supermarkets and several large and small sporting goods stores. Some don't have the same brand, some do, but the size of the store is limited, so there is no monitor. There are only two big supermarkets. Not only selling the same brand, but also having monitoring records, after finding the relevant person in charge, he agreed to save it for Dai Xu and them, Fang Yuan felt that they had been spinning non-stop since lunch, but when they finished turning around the supermarkets and sporting goods stores in an area, it was almost dinner time, and the time seemed to pass by them at a fast-forward speed. The two of them discussed. Decide to have a simple dinner, supermarket opening hours are more common until 9 or even 10 pm. After eating, they can continue to investigate.

When it comes to what to eat, this time they obeyed Dai Xu's taste hobby, bought a hamburger set meal in a fast food restaurant, drove to the next supermarket to be checked, and in the supermarket parking lot, they sat in the car and solved the dinner, so that they could eat enough and save time, which is what they need most at the moment.

"I've been thinking about the incident about Zuo Lishou this afternoon, and I always feel as if there have been some signs, and then I finally remembered," the hamburger was half gnawed, Fang Yuan's stomach was not so hungry, and she made time to discuss a little bit of the case with Dai Xu, she was halfway through her words, turned her head to look at Dai Xu, and found that he had a clear face, "So, at this point, you already have a suspicion, right?" When was it suspected? ”

"From the time I saw the wound, it just didn't show any other signs, so I didn't rush to say it." Now Dai Xu no longer has any worries, he nodded directly, admitting Fang Yuan's guess, "If you sharpen a pencil, only a left-handed person will pinch the pencil with your right hand and sharpen it with your left hand, and even if you sharpen a pencil, if someone hits your elbow, the cuts that may be caused will not be such a wound." I pondered it privately, and felt that the wound, from its position to the direction, was not so much like the knife that sharpened the pencil as it was more like the tip of the carving knife accidentally picked out. ”

When Fang Yuan heard him say this, he also felt that it was indeed the case, since the object of suspicion in her heart was the same as Dai Xu, then she was also much more down-to-earth, the abnormality caused by her lack of concentration during lunch still made her feel a little embarrassed, "By the way, aren't we going to be busy outside late tonight, and then we have to go back to the bureau to work overtime, right?" Wan Qian's mobile phone and computer haven't finished yet. ”

Dai Xu nodded, seeing that Fang Yuan seemed to be very satisfied with this arrangement, he couldn't help but smile and asked, "It's unusual for you to work overtime in the unit at night today?" ”

Fang Yuan coughed lightly, smiled a little weakly, and shook his head: "It's nothing." ”

The two of them spent another two or three hours, transferred to a few supermarkets, these supermarkets are relatively large, the variety of goods is relatively complete, and they actually have the target brand they are looking for, so they found the relevant person in charge one by one, and saved the surveillance video at the cashier within the target date, and then returned to the public security bureau.

As soon as they returned to the Public Security Bureau, there was another new news waiting for them, the test results of the antifreeze came out, Dai Xu carefully read the test report, considering the time problem, he had to leave the inquiry until the next day, and spent the rest of the time with Fang Yuan checking the chat records on the computer and mobile phone, trying to find valuable clues from it. In fact, it was a bit of a discovery, Fang Yuan found a conversation, it was an exchange between Wan Qian and a girl who should be her junior high school classmate judging from the content of the conversation. Wan Qian mentioned that she had a male classmate in the same class, but she didn't say her name, but only said that the other party was very annoying. likes to meddle in things, and actually interferes in the relationship between her and the school grass, it's like a dog meddling with a mouse. Wan Qian also mentioned. This boy's academic performance is not better than his own, his personality is very naïve, and he is self-righteous, and he always plays clever, which makes her feel very annoying.

Such a description, if it had been before, might not have left a deep impression in Fang Yuan's hearts. But after the previous preliminary guess, Wan Qian's description now seems to have drawn a portrait of them. It makes the image in my mind more vivid.

After screening Wan Qian's chat records, Fang Yuan and Dai Xu were not idle, Tang Li was still taking people through the surveillance video near the park, Dai Xu and Fang Yuan carefully browsed the videos transferred back from several supermarkets. I was busy until the second half of the night. Finally found out that in the surveillance video in front of the cash register of a large supermarket, they successfully captured a familiar figure, the time was less than three days before Duan Feiyu's disappearance, at eight o'clock in the evening, the moment when the supermarket was about to close.

This discovery didn't make Dai Xu and Fang Yuan feel particularly excited, mainly because they were too sleepy after a day of tossing. So they each found a duty room to sleep, and got up again early the next morning. Dai Xu went to the neighborhood to buy a lot of early returns, the night before in the public security bureau opened a car colleagues hastily ate a bite, fill their stomachs, and then go to their respective busy, Dai Xu also began to call to inquire, and went to send a few faxes, then set off with Fang Yuan, to the supermarket where the surveillance records were found, and find someone to verify.

The cashier in the supermarket according to the monitoring screen, found the person on duty who was responsible for collecting the money that day, the cashier is also a good memory, looked at the monitoring screen that was replayed, and suddenly remembered the things of the day, he said that he usually likes fitness, when it was close to work, there were not many customers, so he also talked to the buyer a few words, suggesting that he should buy a larger dumbbell for his man to practice fitness, but the other party did not talk, and hurriedly left after paying, He didn't say anything more.

After getting the confirmation, Dai Xu received a call back from an antifreeze agent, saying that the antifreeze brand he represented was indeed consistent with the test results faxed by Dai Xu, and there was a special ingredient in it, which was their company's unique patented technology, and other brands could not have it.

After confirming this matter, Dai Xu felt very excited, he told Fang Yuan about the result, and the two of them returned to the Public Security Bureau, because the monitoring records spanned a long time, so there was no progress for the time being, so Dai Xu and Fang Yuan did not bother them, they went to the key high school in private, and found Teacher Deng again, and asked her for the suspect's usual essays or papers, etc., and brought them back to the Public Security Bureau for handwriting identification, and through more secret means, confirmed the brand of car antifreeze that the suspect's father was used to buying, and none of the results of the investigation surprised Dai Xu, but the motive for the crime was still a little unguessable.

After collecting these evidences, Dai Xu did not act immediately, but waited for a day, and when the next evening came, Tang Li and the others also made progress, and then began to arrange, arranging several groups of people to stop and squat outside several courtyard walls and side gates near the school, while he and Fang Yuan stayed by the main entrance, waiting for the school to study by themselves in the evening.

At eight o'clock, the school bell rang for the end of class, Dai Xu and Fang Yuan got out of the car, entered through the main entrance, and walked straight to the door of the teaching building.

"Huh? Here you go again? Rao Hai was stunned for a moment when he saw Fang Yuan and Dai Xu standing at the door, and then immediately put on a hippie smiling expression, "Who are you looking for?" Our class won't die again, will we? ”

Dai Xu smiled at him, walked over, and put his arm on his shoulder with a relaxed attitude: "Is there such a thing as a dead person, let's go back and talk about it, we came here today to find you." ”

"Looking for me? What are you looking for me? Rao Hai's eyes flickered, but he was still smiling.

"I'm looking for you to understand the situation, let's go, the car is outside." Dai Xu said as he spoke, but he didn't give Rao Hai any room to refuse, almost holding him out, Fang Yuan followed behind them, lest Rao Hai suddenly make any other moves. However, she is obviously overconcerned, maybe she is used to Dai Xu's height and figure on weekdays, but for those who are not familiar with it, such a tall person is still very intimidating. Although Rao Hai was reluctant, he kept muttering and bargaining, but he didn't dare to make any moves.

In addition to the school gates. arranged Rao Hai to sit in the car, Fang Yuan informed the others that they could collect the team, and then drove the car with Dai Xu, driving Rao Hai all the way back to the Public Security Bureau. On the way back to the Public Security Bureau, Rao Hai kept chattering and having nothing to say, talking to Dai Xu and Fang Yuan with a hippie smile, and Dai Xu also chatted with him casually. However, Fang Yuan didn't have any mood in this regard, she felt a tightness in her chest at the thought of what terrible things this big boy had done. There is no way to have a normal conversation with him.

Rao Hai also seemed to be aware of this, so he secretly looked at Fang Yuan from time to time, as if he was speculating about what her attitude meant, but it was a pity. Fang Yuan just ignored him. didn't show any obvious emotions, Rao Hai secretly observed for a while, but he still didn't gain anything.

When he arrived at the Public Security Bureau, there was no suspense, Dai Xu and Fang Yuan took him directly to the interrogation room, as soon as he arrived at the door of the interrogation room, Rao Hai's expression was wrong, he looked nervous. But he still asked Dai Xu with a smiling face: "What is this for?" Take me on a tour? I'm cowardly, don't scare me. ”

"It's fine. Don't underestimate yourself, I think you're quite bold, bigger than the average person. Dai Xu said pointedly, patted him on the shoulder by the way, and half-pushed him into the door of the interrogation room, and settled directly in his seat, before turning around and doing next to Fang Yuan, who was ready to take notes.

"Rao Hai, in fact, you are also a smart person, we didn't go to school to take you to school with great fanfare during the day, but also took into account the impact, as well as your face problem, so, we are already here, let's say what we should say." Ke Xiaowen and Duan Feiyu, don't you want to take the initiative to talk to us? Dai Xu said to Rao Hai calmly that by now, in fact, Rao Hai has no chance to take the initiative, but he still hopes that at the last moment, Rao Hai can take the initiative to admit something with his conscience.

"What are you talking about......?" Rao Hai's smile was almost stiff, but he still had that expression.

"If you don't want to say anything, then let's show you something." Dai Xu sighed, a little disappointed in Rao Hai's attitude, he took out the anonymous note provided by Mr. Deng, as well as Duan Feiyu's "runaway letter", and put both things in front of Rao Hai, "This thing, are you familiar with it?" ”

"I'm not familiar with it, this is not my word." Rao Hai was still grinning.

"Then look at what this says." Dai Xu put the three handwriting appraisals in front of Rao Hai, "After our appraisal, Duan Feiyu's letter of running away from home was not written by himself, but the note that reported Wan Qian's love affair was written by the same person, both of which were written with the left hand, and coincidentally, it is very, very consistent with your usual writing habits, how do you want to explain this?" ”

Rao Hai's face suddenly turned whiter, his lips squirmed a few times, and then he spoke: "I don't know, others asked me to help write it, I didn't think much about it, I just wrote it, I don't know what it was for." ”

This reason was not only lame, but also not reasonable at all, Fang Yuan frowned, and asked, "Then who asked you to help write it, can you say the name?" ”

"That's not good, people ask me not to tell me, I can't betray my friends." Rao Hai replied.

Fang Yuan laughed, laughing angrily: "Then should I praise you for being righteous enough?" At this time, you are not a three-year-old child, you should know what it means to be brought here, and even now, you are still making excuses to prevaricate here, do you think this approach is wise? ”

Rao Hai bowed his head and said nothing, without making any response.

Dai Xu didn't plan to entangle with him more about the incident just now, took back the appraisal certificate and so on, and asked again: "You ran to the supermarket before, and you had dumbbells and sandbags tied to your feet, why did you buy those things?" ”

Rao Hai's body shook on the chair not very obviously, but this time he didn't deny it, but sneered and said, "Oh, yes, I'm in the third year of high school, exercise and exercise." ”

"And if I ask you to take out the dumbbells and sandbags now, will you be able to take them out?" Dai Xu asked again.

Rao Hai's eyes rolled quickly, and he nodded: "Okay, I'll go home and get it now." ”

"Then don't bother, I can contact your parents. Let them find it from home and send it over. Dai Xu leaned on the edge of the table and stared at Rao Hai as he spoke, seeing how he would react.

As soon as I heard this. Rao Hai's previous pretended calmness suddenly collapsed, and he shook his head in a panic: "Don't don't, don't tell me anything, don't look for my parents, can't I beg you?" ”

"The nature of the things you were involved in this time, do you think you can still hide it at this point?" "If we don't have enough evidence." I won't bring you over here. If you're still going to keep your mouth, we can also take surveillance footage of the park. There are also videos from the supermarket to show you, don't worry about our trouble, we are also prepared. ”

After speaking, he put the date and time when Rao Hai and Duan Feiyu appeared together near the park. and the date and time when Rao Hai went to the supermarket to buy dumbbells. They all came out together.

Rao Hai listened to his words, his face was like ashes, and he slowly lowered his head, Fang Yuan wanted to urge him, but was signaled by Dai Xu to calm down, and after about ten minutes, Rao Hai finally spoke, his voice sounded a little trembling. Say, "That'...... So what do you all know? ”

"What you did to Ke Xiaowen, there is also Duan Feiyu. Including Wan Qian, we all know very well that what we need now is for you to tell us why you are doing this. Dai Xu said to Rao Hai in a deep voice.

Rao Hai's face was white, trembling slightly, don't look at him doing so many terrible things, he has been pretending to be calm just now, but in the final analysis, he is only a nineteen-year-old boy, and his psychological quality cannot be as good as that of an old fritter-like criminal, and now when he heard that it was indeed the East Window incident, the whole person immediately seemed to have lost his soul, trembling, and almost bit his tongue several times as if he said: "Because I am under too much pressure, my grades have not improved, and Mr. Deng communicates with my parents every time, I have to say a lot of ugly things, why I have no future after going like this, more and more finished, etc., my parents will beat me when they hear it, and I also want to take the test, but the more nervous and stressful I am, the more I can't do the test, so the more I am sued by Mr. Deng, and I go home and be beaten, which has become a vicious circle. I was very depressed, but I also had self-esteem, and I couldn't show it, so I had to pretend that it didn't matter, and in fact I was about to collapse. ”

"Then you killed Wan Qian because of your pressure that was about to collapse?" Wan Qian's nature was the purest one, so Fang Yuan took out her affairs and took the lead in asking Rao Hai.

Rao Hai shook his head, and said with a sad face: "It's okay, I chased her for so long, she wanted everything to give her, but she hated me this and that, and it turned out that the boy in the outer class was not good at studying, just a face was okay to see, she was fascinated, and she was even willing to play with her." I don't want to see the girl I like become like that, I'd rather let her die like that, at least leave a good impression. ”

After Fang Yuan heard his answer, he only felt shuddering, this ordinary-looking nineteen-year-old boy actually had such a terrible thought in his heart, it was a so-called good impression for him, and he didn't care what it meant to Wan Qian and Wan Qian's family.

"What about Ke Xiaowen and Duan Feiyu? Are you in for the self-enrollment test spot? Dai Xu knew that the exam quota should not be Rao Hai's goal, but he deliberately asked so inducingly, wanting to see his reaction.

Rao Hai shook his head: "Even if the two of them die, it may not be my turn." I'm not actually targeting the two of them, it's just that they happen to be in a similar situation to me, and they are both crazy and want to improve their grades, and if they don't improve their grades, it's hard to live, so it's easier to communicate and easier to take the bait. I just want a few people to die in the class, and then someone will say something about killing and cursing or something, so that the classmates in our class, or the whole school, will feel very frightened and can't learn, but I know what is going on, and I won't be nervous, so I won't be affected, and I can improve my ranking and have a chance to come out. ”

"If you keep the same and everyone else regresses, can this result be called improvement?" Fang Yuan asked.

The corners of Rao Hai's mouth twitched: "Anyway, Mr. Deng can't sue, my parents just don't beat me again." ”

"So how did you get them hooked? If you can say it, take the initiative to say it yourself, don't let us chase after it, this is your last chance to fight for an attitude of confession. Dai Xu said to him with a solemn face.

"I ...... I'm lying to them that I can refresh my mind. Ways to improve memory and improve academic performance quickly. I told them about this in private, one by one, and I said I was using it myself. They didn't believe it at first, so I said, I'm not giving it to you for free, I'm selling it to you, you see if I'm in a particularly good state lately, if you don't believe it, I'll wait to see the results of this exam, but by that time. There is no medicine, regret not looking for me, it's useless to look for me. This was brought back from abroad. ”

Rao Hai knew that the matter could not be hidden completely, so he simply stopped hiding it, and dejectedly explained how he coaxed Ke Xiaowen and Duan Feiyu: "Ke Xiaowen is not easy to be fooled, because of the method I used for Duan Feiyu before. It doesn't work very well. When I got to him, I changed my mind, I had seen in a book about the harm of hydrogen peroxide to the human body or something, I thought of using a syringe, but the syringe hitting something on the body was a bit scary after all, so I deliberately pierced a few needles on my arm and showed it to Ke Xiaowen, which I left when I pierced it at home before. He didn't believe me at first, but then Mr. Deng scolded him. said that if he still didn't have any grades, he would be eliminated from the ordinary class by making an exception, and he was frightened, so he believed what I said. ”

"After you deceived Duan Feiyu, you still want to use him as a smoke bomb to confuse the police, don't you?" Fang Yuan asked.

"I didn't, I'm actually afraid that his family will find out that he ran away from home before, so this excuse is the best, I originally wanted Ke Xiaowen to seem like he committed suicide, and I don't know what went wrong." Rao Hai shook his head, "Duan Feiyu is easier to deceive than Ke Xiaowen, his family is poor, so I found an imported food store, bought a bottle of functional drinks that are all in foreign languages and not in English, and mixed the antifreeze into it and gave it to him to drink, he didn't know it, and he didn't suspect it." At that time, my dad was not at home on a business trip, no one went to my garage, so I stole the key and took him there, I thought that the thing would die soon after drinking, but I didn't expect that I didn't put enough at first, he was just uncomfortable, he didn't die at all, I didn't go to self-study at night, I skipped class and took him to the park, and gave him a bottle of a bottle with a larger concentration, this time it didn't take long for him to die, I tied him with dumbbells or something, and it was late, there was no one in the park, and he was lifted into the lake. ”

"If according to your original plan, Duan Feiyu died of poison in your garage, what are you going to do?" Dai Xu asked again.

Rao Hai pursed his lips and said, "At night, while it's dark, throw him in the park on a bicycle." I didn't think about it that much at the time, I just thought about finding a place for him to hide and drink that drink, and then I thought, fortunately, he was okay at first, I lied to him and said that it was just an adverse reaction after drinking, and I also had it, and he was willing to go to the park with me, otherwise, in fact, I would not be able to handle it. ”

"But don't you want a few people to die in the class, after all, Duan Feiyu just took a long vacation in the eyes of the outside world, and Ke Xiaowen was the only one who died, how do you go about fulfilling your curse?" Fang Yuan still had such a thing to figure out.

"If you can't find me, I'll get another one after a while." Rao Hai's head was so low that it was about to touch the table in front of him.

Fang Yuan was taken aback, and Dai Xu seemed to be a little surprised, so he asked, "Then according to your original plan, who is your next target?" ”

"Zhang Chao." Rao Hai said sullenly, "He is also an unassertive person, I can deceive him." ”

Fang Yuan was shocked and almost couldn't say a word, she always thought that such a serial murder case must have been planned for a long time and had a very deep motive, but she didn't expect that all this actually originated from a junior high school boy, caught between a strict head teacher and a rough parent, because he couldn't bear the pressure and made a "self-help" move, the motive was so simple, but at the same time so cold-blooded and cruel, which was completely unexpected to her, so that she had to distort human nature under pressure, and the cold-blooded and selfish side, with a new understanding.

"Ke Xiaowen's schoolbag, mobile phone, and Duan Feiyu's clothes and pants, have you hidden them?" Dai Xu asked.

Rao Hai nodded: "It's all stuffed under the bed at the head of my house, I originally wanted to find a time to dispose of those things, but then you checked Ke Xiaowen's matter, I was a little scared, I didn't dare to take those things out and go to the park to deal with them, I was afraid that if someone saw it, everything would be over, so I kept stuffing it under the bed and didn't touch it from beginning to end." Originally, I wanted to deal with it as soon as the wind loosened, but now it seems that there is no need for this. ”

After Rao Hai confessed to what he had done, Dai Xu and Fang Yuan notified his parents in accordance with the regulations and went to the Public Security Bureau to go through the relevant procedures, when Rao Hai's parents received the call, they couldn't believe their ears and insisted that it was a prank, and when they repeatedly confirmed that their son had really killed someone, and he had killed three lives in a row, he was almost shocked and couldn't say a word.

After that, Dai Xu and Fang Yuan took Rao Hai to find the deceased's belongings from under the bed in his house, including the carving knife he secretly used to carve the little wooden figure, and the tip of the carving knife really extracted blood residue, which was consistent with Rao Hai's own blood type, confirming Dai Xu's speculation about the wound on Rao Hai's finger. Rao Hai went to identify the crime scene separately, completed other relevant formalities and documents, and the case was finally concluded and could be transferred for prosecution.

However, Dai Xu and Fang Yuan didn't even have a chance to take a breath and rest, and a new case fell into their hands again.

[A new volume will start tomorrow, and the next volume of the story is called "The Red House", as for what it is about...... Hey, hey, hey, let's see you tomorrow (since the last time I saw the explanation of "hey, hey, hey" from Naturalist's Weibo, why are you so guilty of using these three words...... CJ kids, don't look for answers...... Facing the wall! (To be continued......)