After returning the dormitory key to the dormitory manager, the two left the dormitory building.

"What is the probability of this Dong Hua?" Ji Ping asked.

"There is an 80 percent chance that this threatening letter written by Dong Hua." Chen Yiyan replied with his hands in his trouser pockets.

"Boom" mobile phone ringtones.

Ji Ping took out his mobile phone and asked as he walked, "Hey?" What's the matter? ”

"Huh? Okay, I'll come now. Ji Ping hung up his mobile phone and looked at Chen Yiyan: "The bureau called, saying that there was a person named Dong Hua who surrendered." ”

Chen Yiyan stopped and looked at Ji Ping: "What did you turn yourself in?" ”

"Surrender Zhang Sen's case. What else could be going on? Let's go, let's go to the police station together. Ji Ping walked in front of Chen Yiyan.

"No, you go and interrogate, I still have something." Chen Yiyan did not agree to Ji Ping.

"Something? What's the matter? Ji Ping stopped and looked at Chen Yiyan.

"I have some ideas for the case. I'll tell you when I have a conclusion. ”

Ji Ping looked at Chen Yiyan and said slowly: "Okay, then I'll wait for you at the police station." ”

"Okay, I'll message you when I come."

Chen Yiyan saw off Ji Ping at the school gate and got on the bus alone.

The journey is not very long, around six o'clock in the afternoon. Chen Yiyan arrived at the destination of his trip.

"This is the villa area, who are you looking for?" The security guard at the entrance stopped Chen Yiyan.

This security guard is not the same person as a few days ago, maybe something happened in the community, and the last security guard was fired.

Chen Yiyan showed his consultant certificate.

"Police advisor, you're here to investigate the case on the 13th." The house number of the villa where Professor Zhang Sen lives is No. 13.

"Well, can I go in?" Chen Yiyan looked at the security guard.

"That's it." The security guards give way.

Walking to the door of the villa, the blockade had been removed, and Chen Yiyan rang the doorbell twice.

After about 3 minutes, the door opened.

"Advisor Chen? Are there any new developments in the case? Officer Ji Ping said that he would call me to inform me of any new developments. Li Qinlan opened the door and was first surprised to see Chen Yiyan, and then regained her composure.

"Yes, it's a bit of progress, he's going back to the police station now to investigate. I'm here to inform you of this, and then I want to ask you a little bit about your husband. Chen Yiyan deliberately used the description "your husband" to describe the deceased, which is a simple application of language. It's like when you say something, you use something from me, and the other person will feel that they don't care about their own business; But when you use something, the other person will trigger emotional resonance. For example, when a person wants to discuss with his father-in-law about his wife, it will be better to use your daughter than mine. Chen Yiyan observed Li Qinlan's expression.

"Oh, that's right." Li Qinlan understood Chen Yiyan's purpose.

"Can I go in and sit down?" Chen Yiyan spoke.

"Oh, of course, Advisor Chen, please." Li Qinlan opened the door and motioned for Chen Yiyan to come in.

The two of them are under the sofa seats.

"Our police conducted an investigation at Professor Zhang Sen's school today. According to the student, your husband doesn't seem to be behaving in any unusual way with threatening letters lately. ”

"I don't know anything about his job." Li Qinlan looked at the table in front of the sofa and said.

"Oh, by the way, is there water. After asking questions for the day, I was a little thirsty. Chen Yiyan leaned back slightly.

"Oh, okay. I'm going to pour you a glass of water. Li Qinlan got up and walked towards the kitchen.

Chen Yiyan took a look at the appearance of the room, and there was almost no change from when he came before.

"Your water." Li Qinlan handed the glass of water to Chen Yiyan.

"Okay, thank you. Let's put it on the table first, and I'll tell you about the progress of today's police investigation. Chen Yiyan didn't take the water cup.

Li Qinlan put the water cup on the table, sat down and looked at Chen Yiyan: "Okay, you say." ”

"We were investigating the issue of threatening letters, and we suspected that the person who wrote the threatening letter was from the school. Today, I am also investigating this matter. Chen Yiyan looked at Li Qinlan and continued: "We found out that there is a student named Dong Hua, who is a student of Zhang Sen's elective course. He had just gone to the police station and turned himself in. ”

"Turn yourself in? Was he the one who killed Zhang Sen? Li Qinlan asked in surprise.

"Do you know this student?" Chen Yiyan asked.

"No, I don't know."

"Good. I wasn't involved in the interrogation, the police were asking. Then I would like to ask Zhang Sen about other things. Chen Yiyan leaned down and looked at Li Qinlan.

"If you ask, I'll tell you what I know." Li Qinlan expressed cooperation.

"Okay, then I want to ask if your husband has a name in any company." Chen Yiyan asked straight to the point.

Li Qinlan was silent for a while, as if recalling: "He seems to be working as an advisor to the management of a company. ”

"Do you remember what company it was?"

"It seems to be Lisheng Company." Li Qinlan recalled.

"Okay, does Zhang Sen usually have any good personal friends?"

"He doesn't usually go out much, but when he goes out, he goes to the company I said, and the boss of the company seems to be his college classmate, and the two have a good relationship." Li Qinlan replied.

"Oh, that's it, okay." Chen Yiyan picked up the water cup on the table with two fingers, got up after drinking it in one gulp, and said, "Is there still water in the kitchen, I'll pour another glass." ”

"I'll do it." Li Qinlan also got up.

"No, no, I'll do it." Chen Yiyan insisted.

"Oh, right on the kitchen table, that glass kettle." Li Qinlan sat down.

"Okay." Chen Yiyan came to the kitchen with a water glass.

Seeing the glass kettle at a glance, Chen Yiyan poured a glass of water and returned to his seat.

"The police may let you know later." Chen Yiyan drank half of the water he had just poured.

"Okay." Li Qinlan nodded.

"Well, that's it for today. I still have to go back to the police station. Chen Yiyan put the water cup on the table.

"Oh, okay, Advisor Chen." Li Qinlan got up.

"Well, no need to send it. I'll go on my own. Chen Yiyan also stood up, looked at Li Qinlan in front of him and said.

"Okay."

Chen Yiyan turned around to signal goodbye, and Li Qinlan closed the door.

At the entrance of the villa, the security guard saw Chen Yiyan come out and opened the curfew.

"Let me ask you what you do with the garbage here." Chen Yiyan leaned to the window of the security room and asked.

"Someone comes every morning at six o'clock to clean up." The security guard replied.

"Okay, thank you." Chen Yiyan left the community and went to the police station.

Interrogation room of the police station in District 1.

"Team Ping, this kid admits that he wrote a threatening letter, but why doesn't he admit that he killed the victim?" Xiao Zhao asked Ji Ping, who was standing aside, in the observation room opposite the interrogation room.

Ji Ping glanced at his phone: "Cool him down for a while, Chen Yiyan is coming soon." I'll talk about it when he arrives. ”

"Okay." Xiao Zhao opened the door of the interrogation room opposite and motioned for the two interrogators inside to come out.

"Hello Advisor Chen." A passing police officer greeted Chen Yiyan.

"Hello." After the airport case, everyone in the police station knew that Chen Yiyan helped Ji Ping solve the case, but of course they didn't know the details.

"How, what's the result?" Ji Ping walked in front of Chen Yiyan.

"Is Jiang Sheng here?" Chen Yiyan did not answer Ji Ping.

"Ah, what are you looking for him?" Ji Ping was puzzled.

"I'll ask him to check something for me."

Ji Ping didn't ask again: "He should be in the evidence room." ”

"Okay, I'll come to see Dong Hua in a while."

"Okay. I'll be waiting for you in the observation room. ”

Chen Yiyan came to the evidence room: "Officer Jiang." ”

"Advisor Chen." Jiang Sheng looked up at Chen Yiyan: "Is there something wrong?" ”

"You can check this for me." Chen Yiyan handed Jiang Sheng a piece of things: "When will it come out." ”

"Do you compare it with the evidence?" Jiang Sheng took the thing and asked.

"Yes, contrast."

"That should be quick, it should be out tomorrow morning." Jiang Sheng replied.

"Okay, I'll get the results tomorrow."

The door to the observation room opens.

"Explained?" Ji Ping saw that it was Chen Yiyan who came in.

"Well, what's going on with Dong Hua." Chen Yiyan looked into the interrogation room. In the interrogation room sat a young man in his mid-twenties, with an ordinary hairstyle with oblique bangs, black-rimmed glasses, and a white T-shirt with his head bowed.

"He admitted that he wrote the threatening letter, but did not admit that he killed Zhang Sen." Ji Ping also turned his head to look at Dong Hua.

"Why did you write a threatening letter?"

"Yes, but he won't say." Ji Ping crossed his hands on his chest.

"I'll ask." Chen Yiyan left the observation room without Ji Ping's consent.

After a while, the door to the interrogation room opened. There was no air conditioning in the interrogation room, which was a bit hot. Chen Yiyan brought a water cup and put it in front of Dong Hua: "Do you want to drink water?" ”

Dong Hua glanced at Chen Yiyan, picked up the water cup without saying a word, and took a sip.

"Do you smoke?" Chen Yiyan continued to ask.

"No." Dong Hua spoke.

"I'm not here to ask you about Zhang Sen's killing, I'm here to ask you about threatening letters." Chen Yiyan pulled out the chair opposite Dong Hua and sat down.

Dong Hua turned his head and didn't look at Chen Yiyan, with a very firm expression.

Chen Yiyan saw this expression: "Do you mind if I smoke?" ”

Dong Hua turned his head this time, and he shook his head.

Chen Yiyan lit a cigarette and put it in the ashtray next to him.

"I know you wrote the threatening letter, and you admit it, right?" Chen Yiyan wanted Dong Hua's answer.

"Yes, I wrote it." Dong Hua looked at Chen Yiyan.

"I've read the content of your threatening letter, but we asked a lot of people, and they all said that Zhang Sen was honest and modest. It's not like what you wrote in your threatening letter. Chen Yiyan stared at Dong Hua.

Dong Hua's eyes became a little sharp, and he turned his head and said, "Hmph." He's just a brute. ”

"Brute? Why do you say that, and what did he do? Chen Yiyan picked up the cigarette on the side, took a puff, and then spit out the cigarette.

Dong Hua still lowered his head to the side and did not speak.

Chen Yiyan put the cigarette back into the ashtray again, and he said slowly, "I know what he did, and I know why you wrote these threatening letters. ”

Hearing Chen Yiyan's words, Dong Hua turned his head sharply to look at Chen Yiyan.