The scene of the incident was a reservoir next to the Lingnan Sports Centre, which is very close to the school bus stop and the MTR station. When Ho arrived at the scene of the crime, the body of the deceased had been fished out of the pond.

He Jiahui stepped forward to take a look and found that the deceased was a middle-aged man in his forties. His hands and feet were tied, and he had a dumbbell tied to his leg.

"The deceased this time is a bit old. If you're in your forties, you're probably not a college student! He Jiahui said secretly in his heart, and at the same time felt a little confused.

Ho Ka-fai bowed down and carefully examined the deceased's condition.

On the side of the deceased's mouth, there is some mushroom-shaped foam, which is one of the typical physical characteristics of the drowning victim.

In the process of drowning, cold water enters the trachea, which will irritate the tracheal mucosa, causing the trachea to secrete a large amount of mucus, and then form a fine and uniform white foam. Because these foams are rich in mucus and have high stability, they are not easy to burst and eventually adhere to the mouth and nostrils.

At this time, Ma Jun also came to the front.

"Has the identity of the deceased been confirmed?" He Jiahui asked.

Ma Jun nodded and opened his mouth to introduce: "After alumni identification, the deceased's name is Cai Zhixiang, who is the director of the property management office of Chinese University. ”

"Cai Zhixiang? What are the three words? He Jiahui asked immediately.

"Cai is the Cai surnamed Cai, Zhi is the ambition with great ambitions, and Xiang is the Xiang of flying." Ma Jun replied.

"These three words don't carry water!" He Jiahui frowned.

The previous three deceased, their names all have five elements corresponding to the method of death, according to the order of the five elements, this time it is the turn of the water, the deceased did die in the pool, but in his name, there is no water.

Ma Jun spoke; "Not only did the deceased have water in his name, but he wasn't a member of the student council, which was not the same as the three previous deceased."

"What about Zhang Xingjie? Aren't we watching him twenty-four hours a day? Has he been out of our watchful eye? He Jiahui asked.

"Last night, it was impossible for Zhang Xingjie to come over to commit the crime." Ma Jun continued with certainty: "At about half past ten last night, Zhang Xingjie was sent to the hospital because of acute appendicitis, and then underwent surgery in the emergency department, so he was in the hospital all night. ”

"In other words, the murderer this time is definitely not Zhang Xingjie." Ho Ka Fai fell into deep thought.

Ma Jun continued to ask: "We have locked up Zhang Xingjie before, but this time Zhang Xingjie is impossible to commit a crime, what do you think of this case?" ”

"I think there are three possibilities." He Jiahui stretched out three fingers and continued; "The first possibility is that Zhang Xingjie is not the only murderer, he also has an accomplice, and this time it is an accomplice.

The second possibility is that we mistook the target, Zhang Xingjie is not the murderer, and now the real murderer has come out to commit the crime again. As for the third possibility, it is that someone imitated the crime. ”

"Copycats?" Ma Jun's brows furrowed, and he also began to think about this possibility.

He Jiahui continued: "We can think of the five elements to kill people, and others may also think of it. And then take the opportunity to carry out imitation crimes, which is a possible thing.

However, the detection of sevoflurane in the bodies of the first three deceased, we did not announce it to the public? If it is a parody killing, then the murderer should not know about heptachloroxane.

So we only need to test whether the deceased has sevoflurane in his body to know whether this case is a parody homicide. ”

He Jiahui said, looked up and looked around, and then asked, "Is there surveillance around here?" ”

"How can there be surveillance in the reservoir?" Ma Jun also looked around, and then said: "There is Zhongzhitang Restaurant next to it, as well as Chongji Academy, I will send someone to take a look, I hope that the surveillance there can capture the situation in the pond!" ”

He Jiahui continued: "This murder is different from the previous three times, this time there is no fire, no typhoon, and no rain, and the traces left by the murderer should not be destroyed, maybe it can bring us new clues." ”

……

The medical examiner brought back the body of the deceased for an autopsy, the forensic examiner began to gather information from the scene, and the police began to investigate the deceased's interpersonal relationships.

After some investigation, Ma Jun brought the details of the deceased:

"The deceased, Cai Zhixiang, 44 years old, was the director of the property management office of the university, married, his wife was a bank clerk, the couple had a good relationship, and they had a daughter who was in primary school.

The deceased's financial situation was normal, he and his wife took out a joint loan to buy a house, and repaid it on time every month. Apart from a mortgage and credit cards, the deceased had no other debts and had not borrowed money from loan sharks.

In addition, there are more than 200,000 deposits on the deceased's bank card, which can be judged that the deceased's financial situation is good, and his death should not be caused by financial disputes.

The deceased also had no bad habits, did not gamble, did not buy horses, did not touch drugs, and occasionally bought the Mark Six lottery with his colleagues, but never won the jackpot.

The deceased's life was very regular, he commuted to and from work on time, his daily interpersonal interactions were also normal, and he had no enmity with anyone. His usual social range is also mainly in school. ”

"It sounds like this Cai Zhixiang is just an ordinary faculty member, and there are no highlights in his life at all!" He Jiahui nodded irritably, the more ordinary people are, the more difficult it is to determine the direction of the investigation.

Ma Jun continued: "We have looked for the wife of the deceased, and according to her confession, at six o'clock yesterday afternoon, she received a text message from the deceased, saying that she was going to have dinner with her colleagues and did not need to wait for her to eat.

At about nine o'clock in the evening, she received another text message from the deceased, saying that they would go singing together after eating, and asked her to go to bed first, not to wait for her.

After receiving the text message, the deceased's wife immediately called the deceased's phone, but the other party did not answer, but hung up directly, and then sent another text message saying that the mobile phone was out of battery.

At 12 o'clock in the evening, the deceased's wife called the deceased's phone again and said that the phone had been turned off, and the deceased's wife thought that the deceased's mobile phone was out of battery, so she fell asleep by herself.

This morning, when the deceased's wife woke up, she found that the deceased had still not returned, and she called the deceased's mobile phone or turned it off, and called the deceased's office, but no one answered. After that, she went to work, and it was not until we were notified that the deceased had been killed. ”

"Did you find the deceased's mobile phone at the scene of the crime?" He Jiahui immediately asked.

"You're really to the point right at once." Ma Jun continued: "We found the wallet and keys on the deceased's body, but we did not find the deceased's mobile phone. ”

"Could it be that you fell into the pond?" Ho Ka Fai then asked.

"Someone has been sent to salvage it, but nothing has been found so far." Ma Jun paused, and then asked, "I also asked the deceased's colleagues, and they said that there was no dinner last night, and everyone left after work. ”

In other words, the mobile phone text messages received by the deceased's wife are likely to have been sent by the murderer. After getting off work yesterday, the deceased was already controlled by the murderer, and then the murderer used the deceased's mobile phone to send text messages to the deceased's wife.

In this way, the wife of the deceased thought that her husband was having dinner and singing with his colleagues, so she would not suspect that the deceased had an accident, and would not come to the school to find someone or call the police, and the murderer would have enough time to sink the deceased into the pond in the dead of night. ”

He Jiahui said and muttered for a few seconds, and then asked, "What about monitoring?" Has the pond been captured by surveillance? ”

Ma Jun shook his head: "There is no monitoring of the pond, we can only go to the buildings around the pond to check, but we find nothing." No monitor will be idle and photograph the pond. ”

He Jiahui continued: "Did the surveillance of the nearby road capture the deceased or other suspicious people passing by? ”

Ma Jun still shook his head, and said helplessly: "It's not that you haven't been to Chinese University, the monitoring system there is not much installed, and it is basically installed indoors, on the road outside, where is the monitoring for you to check!" ”

The density of public cameras in Xiangjiang is not high, and the Chinese University is built on the mountain, the government has allocated the entire mountain to the Chinese University, where there is a flat place on the mountain, a building is built, and the roads in the university are also carved out of the mountains and forests, and there is no monitoring coverage.

Ma Jun continued: "Forensic evidence collected footprints on the bank of the pond, as well as a set of wheel marks, which look like suitcases, and it is estimated that the murderer used suitcases and other things to transport the deceased to the edge of the pond." ”

"Suitcase? This may be the direction of investigation. If you can find the person who pushed the suitcase, there may be a clue to the murderer. He Jiahui said immediately.

"It's harder, too." Ma Jun continued: "The reservoir where the crime occurred, next to the school bus station of the Chinese University, opposite is the MTR Chinese University station, almost every MTR stop, someone will push the suitcase by, if you check one by one, it is almost impossible." ”

"Can the dumbbells tied to the legs of the deceased find their source? Next to the place where the crime occurred is the gymnasium, where will the dumbbells come from? He Jiahui asked again.

"The dumbbells are old and are unlikely to be traced through sales information. I also asked the cannon to go to the gymnasium to check, and there were no dumbbells missing in the gym recently. Ma Jun replied.

The two fell silent at the same time, and although it did not rain this time, they found the traces left by the murderer, but these traces still could not allow the police to lock down the identity of the murderer.

At this moment, Ma Jun received a text message on his mobile phone.

Ma Jun looked at the information on his mobile phone and said, "The forensic doctor has a result." The time of death of the deceased was between 3 and 4 a.m., and the cause of death was suffocation caused by a large amount of fluid entering the respiratory tract, that is, drowning. Moreover, the body of the deceased was tested for the residue of sevoflurane! ”

"That would rule out copycating." He Jiahui nodded with a solemn expression, and continued: "Since sevoflurane was detected in the deceased's body, it means that this is also one of the serial murder cases, and the murderer is the same person, or the same group."

But the problem is that this case is quite different from the previous three cases. First of all, the deceased's name does not contain water, which is equivalent to the murderer changing the logic of the previous crime.

Secondly, the deceased was not a member of the student council, or even a student, but a faculty member. This is tantamount to the murderer changing his habit of choosing the target of the crime. This is not common in serial homicide cases.

According to my previous inference, the murderer targeted the student union, and then chose a person with the five elements of gold, wood, water, fire, and earth in his name, and used the corresponding five elements to kill him, but Cai Zhixiang's death overturned these two inferences at the same time.

So I have a new idea, the murderer is not targeting the student union organization, but the individual, that is to say, the murderer is actually going to kill these four people, but the first three deceased happen to be in the student union. ”

Ma Jun thought for a moment and spoke; "But we have checked the interpersonal relationships of the deceased, and none of them have enemies, why did the murderer specifically target the four of them?"

He Jiahui replied: "Serial homicides, if the crime is committed against an individual, it is nothing more than two situations, the first situation is that each deceased is related to the murderer, and the murderer has a grudge against each deceased, and then kills them one by one.

The second situation is that there is a correlation between individuals. For example, the murderer will commit a crime against a certain group of people with certain characteristics in a specific weather, at a specific time, in a specific situation, or in a specific environment.

For example, the famous Rainy Night Butcher case, isn't this the case? And this type of offender often has psychological problems or antisocial personality. ”

"You mean, these four dead are related? Is this correlation the motive for the murderer's killing? Ma Jun thought for a moment, and then said:

"The first three deceased are okay, they are all members of the student union, but the fourth deceased is the director of the property management office, and he has no relationship with the first three!."

"That's what we need to look into!" He Jiahui paused in his voice and continued; "Although there are more than 20,000 faculty members in Chinese University, everyone is in the same school after all, and they can be regarded as looking down and not looking up.

Will the life circles of the four deceased have a common intersection point? Will there be any business dealings between the Students' Union and the Property Management Office? These could all be related to the four deceased. ”

"Makes sense, let's go, let's go to Chinese University again!"

With a new direction of investigation, Ma Jun immediately regained his vitality.

……

This time, Ho Ka Fai and Ma Jun came to the property management office, which is where the fourth deceased worked. In charge of receiving them was a teacher surnamed Wang.

After briefly explaining the intention, He Jiahui asked straight to the point: "Teacher Wang, will the usual work of your property management office involve the student union?" ”

Teacher Wang replied: "Our property management office is responsible for the property management of the whole school, in addition to the routine work of removing garbage, repairing facilities, and maintaining equipment, it also includes the approval of venues for school activities.

For example, if there is an exhibition or award ceremony in the school, then our property management office will be responsible for preparing the venue for the event.

For example, if a student organization wants to hold an event, it also needs to apply to us for a venue, and after we approve it, they can use the corresponding venue.

There are many student organizations in our Chinese University, such as various interest and public welfare groups, including the student union, and the student union usually holds more activities, so they often come to us to apply for venues. ”

"In addition to applying for venues, does your business have anything else to do with the student union?" He Jiahui asked again.

Teacher Wang thought for a moment and replied, "There shouldn't be any!" We, the administrative departments, are for students and faculty, and we can't provide any other services than normal property management and event venues. ”

"Mr. Wang, can you give us a copy of the application for the event venue in the past year?" He Jiahui asked again.

"No problem, we have an archive of the use of venues for all activities in the school, and I will find you immediately." Teacher Wang replied.

……

After returning to the Serious Crime Unit, Ho Ka-fai began to review the information provided by the Property Management Property Office.

There are more daily activities held in Chinese University than Ho Ka-fai imagined, and most of them are organized spontaneously by student groups.

For example, the photography club will hold a photography exhibition every month, for example, the science and technology club often has robot competitions, and the drama club needs to rehearse every week, which requires applying for a venue.

The activities held by the student union are indeed the most, almost every week, there will be a theme activity, and there will be two activities a week when it is frequent.

Suddenly, a piece of venue usage information entered He Jiahui's field of vision.

"There seems to be a problem with the use of this venue!"

The location of the crime was changed from a swimming pool to a pond, and I checked the map and found that the location of the reservoir was a more suitable location for the crime.

(End of chapter)