Teresa, a senior chemist at the Central Police Station, collected many fingerprints at Gu Xiaolan's home, half of which did not belong to Gu Xiaolan or her agent.

After returning to the police station, they can be compared to see if they are Zhao Dongsheng's fingerprints. If not, then they are most likely the murderer's fingerprints.

Teresa collected a few short hairs by the bathtub in Gu Xiaolan's home, which are very similar to the short hairs collected by Awei, Fang Zhenyue and Jiayi at the surveillance point on the mountain road.

"The stalker may have bathed in this bathtub." Teresa conducted a more in-depth investigation and evidence collection.

Next, it was confirmed that the stalker may have used Gu Xiaolan's toothbrush and water cup, and even slept in Gu Xiaolan's bed.

Because Gu Xiaolan had not lived at home recently, and the police had been waiting outside Gu Xiaolan's house, but no suspicious people were found.

So the stalker may have moved in before that, and after Gu Xiaolan found out that someone might have broken into her house, he never came back.

"This stalker has a strong sense of anti-detection." Liu Jiaming turned around and muttered to Uncle Jiu.

If the stalker alarmed Gu Xiaolan, it would also be likely to alarm the police. At this time, it would be too risky to illegally break into Gu Xiaolan's house.

"Sir Fang, we only found half a shoe print outside Miss Gu Xiaolan's house, and we suspect that the stalker changed his shoes after entering the house. We will make a detailed comparison between this half footprint and the footprint collected by Awei at the surveillance point on the mountain road outside the house after returning to the police station." Teresa straightened up and said seriously:

"If the stalker's footprints are consistent with the footprints collected at the big bend of Shi Xun Road, the footprints collected in the yard of the No. 6 Villa on Shi Xun Road, and the footprints collected at the burial site, then it can be basically confirmed that the murderer of Zhao Dongsheng is the one who followed Miss Gu Xiaolan."

"Thank you for your hard work." Fang Zhenyue nodded.

The two turned around and saw Tannen sitting on the sofa chatting with Gu Xiaolan. He asked Gu Xiaolan if she had any impression of the person he profiled while taking notes.

"An expert sent by the higher-ups?" Teresa nodded at Tannen and turned to ask Fang Zhenyue.

"Yes, a criminal psychology expert who studied in the UK. Inspector Qiu Susan and I both wanted to go to the UK to study a short-term course in this subject, and we didn't expect that the superiors would send us an expert in this field." Fang Zhenyue nodded.

"These are all things exaggerated by American movies and novels." Teresa obviously didn't think criminal psychology and profiling were reliable.

"Combined with actual combat experience, some deduction methods, conclusions, a large amount of data compiled in literature, and in-depth research on criminal psychology are still interesting. We can get the essence from the dross, and perhaps we can polish jade with the stones from other mountains." Fang Zhenyue's attitude is very open. "Criminal Psychology" is also mentioned in the Hong Kong Police Academy. However, this subject is constantly innovating, and it is still meaningful to go abroad to get in touch with the latest theories and conclusions.

"Don't we have many physical laboratory departments, microscope laboratory departments and other departments in the Scientific Forensic Department? The superiors want to transfer him to the Scientific Forensic Department, and several forensic laboratory technicians in our police station are opposed." Teresa hammered her waist, scanning Gu Xiaolan's house with her eyes to find out if there is anything missing, while chatting with Fang Zhenyue.

"Why?" Fang Zhenyue raised his eyebrows.

"On one side is absolute objective evidence, and on the other side is subjective evidence. The Forensic Department does not accept criminal psychologists and profiling experts. They don't get along." Teresa shrugged.

Fang Zhenyue chuckled, nodded at Teresa, and walked towards Tannen.

"What do you think?"

Fang Zhenyue and Jiayi, who was also paying attention to Inspector T, looked at each other and looked at the notebook in Inspector T's hand.

Tannen looked up and smiled. There was no clue for the time being. Gu Xiaolan did not remember meeting anyone with a special appearance or figure.

In some occasions when meeting admirers, Gu Xiaolan met too many weird people and it was really difficult to recall any meaningful clues.

"Sir, when can we catch this stalker? I don't even dare to go home now. I don't feel at ease even if I change the locks." Gu Xiaolan's eyes were red, and she looked at all the detectives helplessly.

When she thought of the pervert using her things and sleeping in her bed at home, she wanted to burn down the house.

Even if she wanted to sell it now, it would be very difficult.

The gossip magazines published the news that she was harassed by the stalker. Everyone knew that the house was not clean, and the price plummeted. She suffered a lot.

"The police will guarantee your safety and solve the case as soon as possible. Don't worry." Fang Zhenyue comforted the victim, and led everyone to do the final finishing work, and then the team was neatly dismissed.

Colleagues from the Forensic Investigation Department rushed back to the Central Police Station to do a comparison and test so that they could give the information to Fang Zhenyue's team as soon as possible.

Everyone wanted to solve the case as quickly as possible, and rushed forward like a twist.

Fang Zhenyue "kidnapped" Ah Wei and immediately led everyone to conduct a large-scale survey based on the old residence of Gu Xiaolan written in Jiayi's notebook.

Although those houses are now occupied by others and cannot be searched, the detectives took Ah Wei around many times to find the "best surveillance points" of these old residences.

Sure enough, in some places, although moss had grown, they had been worn flat by people standing for a long time and were not easy to be discovered. Excellent "surveillance squatting points" were found - this way of looking for clues was not wrong.

Although it was too long ago, Ah Wei did not find any clues in these places.

But the detectives found some residences where they could monitor Gu Xiaolan's residence -

the murderer might have lived in one of them, blending himself into the darkness with an old telescope at night and spying on Gu Xiaolan.

"We all thought that Gu Xiaolan was a star before, so the stalker must have discovered Gu Xiaolan through TV programs, newspapers, magazines, and advertisements, and started to follow and fantasize about her."

Jiayi thought that everyone might have fallen into a misconception before:

"But in fact, two years ago, Gu Xiaolan had just debuted and was not very popular. At that time, she lived in Sham Shui Po, a place where all kinds of people mixed together.

"Is it possible that the stalker had actually encountered Gu Xiaolan by chance when she was not famous because he lived not far away, or had locked onto her in other daily environments?

"For example, when taking a morning or evening walk, he encountered her in the garage and had a collision with the murderer's car?

"Among these, the most likely possibility is that the stalker lives in a place where he happens to be able to see the house where Gu Xiaolan lived in her early years, right?

"A stalker would initially look for a particularly convenient, simple, and easy target. So a pretty girl who happens to live in the building opposite is obviously a good prey."

Following Jiayi's train of thought, the detectives wrote down the building numbers of all the units that could monitor Gu Xiaolan's residence through telescopes.

Jiayi couldn't help but expand her thoughts and turned to ask Fang Zhenyue:

"Brother Yue, do you think that this stalker initially chose Gu Xiaolan? Or, did he only choose Gu Xiaolan?

"Is it possible that there were several other women who had been stalked before he targeted Gu Xiaolan?

"At that time, his tracking and surveillance skills were poor, and he was discovered... Then, the police station may have a report record about tracking."

Fang Zhenyue nodded, and added: "But the fingerprints we have collected so far have not been matched to the murder in any police station... In other words, if this stalker was discovered and driven away by the victim's police report, it is very likely that the process did not reach the step of entering the police station to record fingerprints, and the case was closed after communication and mediation on the spot."

"Yes, yes." Jiayi nodded vigorously.

"Jiaming, when you go back, check all the tracking reports of the police force 2 years ago and 6 years ago that were successfully closed after mediation, and see if there are any people living near Gu Xiaolan's old rental residence among these people." Fang Zhenyue turned around and gave instructions to Liu Jiaming.

"Yes, sir." Liu Jiaming responded immediately.

"After we have a meeting with Inspector T, Sanfu, go find Gu Xiaolan and take a statement. Ask her if she had any conflicts with the neighbors when she lived in the old rental house, or other people and things that left a deep impression on her. Maybe we can get some useful clues." Fang Zhenyue continued to appoint people.

"Yes, sir." Sanfu also accepted the order respectfully.

"Gary, after we have a meeting with Inspector T, you can come to Gu Xiaolan's old residences. Check the units above and below Gu Xiaolan and the ones next to her to see if there are other young beauties who lived here at the same time as Gu Xiaolan. If there are, take their statements and ask them if they have been followed or monitored." Fang Zhenyue leaned forward and pointed at Gary's head in the crowd.

"Yes, sir." Gary stepped forward and nodded.

Tannen stood behind the detectives, constantly recording the detectives' investigation process, Fang Zhenyue's way of thinking, Yi Jiayi's way of thinking, etc., trying to find out where his expertise could assist them, or where his thinking contradicted theirs.

On the way back, Tannen looked through his notes and found that the way Hong Kong detectives handled cases was different from what he had imagined, the simple or even clumsy human wave tactics.

Although people would not say that their logic relies on criminal psychology and profiling, they actually use it.

For example, the deduction made by Yi Jiayi actually mentioned the professional content in [Geographical Portraiture]. She judged that the murderer was a hunting stalker who started from her own residence and spread out to the surrounding areas to look for hunting targets.

He marked this place in the notebook, and thought again, Yi Jiayi just didn't know that she used the professional knowledge of criminal psychology in her own thinking.

If he, as an expert in this field, imparted more systematic knowledge to her, would she be able to be more perfect, easier and faster when doing these thoughts and reasoning?

Thinking of this, Tannen looked up through the rearview mirror and glanced at Yi Jiayi sitting in the back seat. He could already imagine her eyes filled with surprise and admiration when he told her these things.