Regarding the case of Ling Xiang's fall from the building, Mu Zi himself narrated it like this:

At around 9 p.m. on April 13, Mu Zi was studying at night in the classroom of the second class of the third year. Because the homeroom teacher is usually not in the classroom during the first half of the third evening self-study class, the students go out to the toilet or make a phone call or something at will.

At 9:12, Mu Zi inexplicably received a text message from Ling Xiang: I already know your secret, now let's go to the rooftop and talk!

After receiving this text message, Mu Zi looked up at Ling Xiang's seat in surprise, only to notice that Ling Xiang was not in the classroom at that time.

Combined with the anonymous letter he received a few days ago, Mu Zi naturally thought that the anonymous letter was Ling Xiang's ghost, and what Ling Xiang wanted to talk to her about must be related to Jiang Xiaoyan's disappearance. Mu Zi didn't know what Ling Xiang wanted to do to her, but she only knew that if this matter reached the ears of her classmates, her life at school would become even more sad.

In order to solve this annoyance in his heart as soon as possible, Mu Zi did not hesitate, and immediately walked out of the classroom to the rooftop of the building. Considering that the guardrails on the roof are in disrepair and pose a safety hazard, theoretically speaking, the school prohibits students from going to the rooftop. However, the small door to the rooftop has not been locked, so occasionally students will run to it to steal a cigarette or talk about love.

When Mu Zi arrived at the rooftop, he didn't see Ling Xiang's figure. At first, she thought she had been tricked by Ling Xiang's prank, but after a closer look, she found a mobile phone and a bloody stone on the edge of the rooftop on the east side.

This kind of déjà vu scene in the TV series makes Mu Zi feel very bad. She didn't know what she was thinking, but she couldn't help but look downstairs. At this look, she suddenly gasped, because Ling Xiang, who had asked her to meet on the rooftop, had fallen to the edge of the flower bed downstairs, not moving, like garbage thrown from a high altitude.

At that moment, she felt like her mind went blank. She froze there, not daring to confirm Ling Xiang's life or death, not daring to move, not daring to shout, not even daring to blink, not daring to breathe. After three or four minutes, she slowly took out her mobile phone from her pocket and dialed Xia Jinyu's number.

After receiving Mu Zi's call for help, Xia Jinyu immediately rushed to the rooftop. After learning what happened, he first called the police, because judging from the situation at the scene, Mu Zi would be investigated by the police as a key suspect anyway. Rather than concealing the truth and being found afterwards to explain and arouse deeper suspicion, it is better to take the initiative to call the police. After reporting to the police, Xia Jinyu quickly dialed Xia Shi's phone again, because he knew that the police who took over the case would not believe Mu Zi's words so easily, and the only person who could save Mu Zi and restore Mu Zi's innocence was Xia Shi.

The above information was relayed by Xia Jinyu to Xia Shi and Gu Song, and he firmly believed that this was the truth of the matter. But in the eyes of the police, there is obviously another version of what happened:

At 9:12 p.m. on April 13, 2016, Mu Zi received a text message from Ling Xiang in the classroom and immediately rushed to Taiwan to make an appointment. The two girls had a heated argument while chatting. In a fit of rage, Mu Zi smashed Ling Xiang's head with a stone, pushing her off the roof while she was dizzy, causing her to die.

Mu Zi had both the motive and the time to commit the crime, and there were text messages from Ling Xiang on her mobile phone, and Mu Zi's classmates were able to prove that she left the classroom during the evening self-study.

All of this unfavorable evidence points to a very clear answer: Mu Zi is the murderer who killed Ling Xiang.

If he had to let Xia Shi choose one of these two versions, he would certainly like to believe that Mu Zi was wronged. But the problem is that he is a policeman and can't act with emotion like Xia Jinyu. Everything must be evidenced, not a sentence of "I believe you did not kill anyone", and the case was solved in this way.

Soon after Mu Zi was taken away by the police, Xia Jinyu was also brought back to the criminal police team to cooperate with the police to make records. The medical examiner conducted a preliminary autopsy on Ling Xiang's body and confirmed that Ling Xiang had fallen from the stairs after being attacked by the murderer. As for whether the murder weapon that attacked Ling Xiang was the stone on the rooftop, further confirmation is needed.

After the bodies were pulled away, the students dispersed (in fact, it was time to get out of school). The huge campus has returned to its former calm, as if everything that happened just now is just a condiment to the boring study life.

Ling Xiang, the girl who loved to talk about other people's privacy the most in her life, will soon become the focus of discussion by the whole school. Isn't it cruel to end the life of an eighteen-year-old in such a way? Even though she was open-mouthed and had deeply hurt her classmates with her words, the punishment of death was still too severe for her.

It was late at night, and the entire campus was shrouded in darkness. Only a few police officers were left at the scene to put some finishing touches, and everyone else had already evacuated the school.

Gu Song and Xia Shi hadn't left yet, they were standing by the flower bed of the teaching building, looking up at the rooftop above their heads, and they had already reinterpreted the two versions of what had happened many times in their minds.

After a long time, Gu Song took the lead in breaking the silence and said: "If this is a well-planned conspiracy, there must be a deep grudge between the murderer and Mu Zi. He did not hesitate to frame Mu Zi by killing people, and his heart must have been filled with hatred. I think anonymous letters are always a clue that can't be ignored. Perhaps the murderer who framed Mu Zi was the one who hid the anonymous letter. ”

"Listen to what you mean, are you more inclined to Muzi being wronged?"

"Don't you think so?" Gu Song was a little surprised by Xia Shi's reaction, he thought that Xia Shi would be on Mu Zi's side no matter what.

"I'm afraid that emotional things will affect rational thinking, so ......," Xia Shi paused, "so I don't have a clear idea yet." ”

"When you tell yourself not to be influenced by your feelings, you have been influenced."

"What do you mean by that?" Xia Shi turned his head to look at Gu Song, with a puzzled expression on his face.

"You become hesitant and don't dare to make assumptions and inferences easily, and that's what you are influenced to do. Because you don't usually behave like that. Gu Song explained as he walked towards the door of the teaching building, "I think it's not a bad thing for an animal like a human to be affected by emotions occasionally. In this way, you first have a belief in your heart, that is, the person I believe will never kill. Next, you try all kinds of ways to prove that the person you believe is not the murderer, which is actually the same reason that we go to great lengths to find evidence to prove that a person is the murderer. ”

"You're right." Xia Shi agreed, "Maybe it's because I want to prove that Muzi is not a murderer so much that I'm afraid that the result of the proof is a false proposition, so I unconsciously retreat in my heart." ”

"Okay, I'll now talk about the two most basic doubts in this case, and you should be relieved after listening to it. First of all, it is intuitive, all the unfavorable factors in this case point to Mu Zi, and all the evidence is too obvious, it is like a pre-arranged play.

"The second is logical. After the case, Mu Zi first contacted Xia Jinyu, and Xia Jinyu decided to call the police after weighing, which of course was agreed by Mu Zi himself. Assuming that Mu Zi is the murderer of Ling Xiang, her agreement to call the police is equivalent to her intention to surrender to the police. But after the police came, she didn't admit that Ling Xiang was killed by her, so there was a logical contradiction. Assuming that Mu Zi is not the murderer......" Gu Song smiled and said, "There is no need to assume this, this is exactly the result we want." ”

Xia Shi's expression also relaxed a little. He thought for a moment and asked Gu Song, "What if the thief shouts to catch the thief?" As soon as he finished asking, he shook his head and answered to himself, "When a thief shouts to catch a thief, it is generally when the evidence points to others, at least there will not be so many unfavorable factors pointing at himself at the same time." If Muzi is the murderer, she will either call the police and turn herself in to the police, or destroy the evidence and try to escape. It will not be the same as now, there will be an embarrassing situation of calling the police but shouting wronged. So to sum up, it is very likely that Mu Zi was framed by someone. ”

"After we have strengthened this belief, we have to find out who framed Muzi." Gu Song turned on the flashlight and walked into the pitch-black teaching building, Xia Shi followed closely behind him.

Gu Song continued: "From the analysis of the content of the anonymous letter and text message, the so-called secret in the text message should refer to the disappearance of Jiang Xiaoyan mentioned in the anonymous letter. In other words, the person who hid the anonymous letter and the person who sent the text message should be the same person, that is, the murderer who framed Muzi. Since this person had the opportunity to hide the letter in Mu Zi's review materials, and was not noticed by the people around him, this person was most likely to be Mu Zi's classmate.

"Then when Ling Xiang was killed, the students who were also not in the classroom were likely to be the murderers who framed Mu Zi. Of course, for the sake of safety, we should make a list of all the senior high school students who were not in the classroom at the time of the crime to see if they had the opportunity to hide the anonymous letter and whether they had a certain connection with Jiang Xiaoyan. I don't think there will be more than three suspects who meet these criteria. ”

The two men talked as they walked down the stairs to the rooftop deck on the roof. Xia Shi's mind was much calmer than before, he didn't want to see Xia Jinyu show such a sad and helpless expression, and he didn't want the girl Jin Yu liked to suffer injustice. It's been eleven years, and he has been guarding this wounded soul with his strength and bravery for eleven years. Even if the other party has grown up, he still has to stick to his original promise:

"From now on, this is your home, and I am your brother. I'll protect you no matter what happens, and I'll never let you be hurt by anyone again......"