"If you say that, it's very likely." Chen Yufei suddenly realized, "Then the theft of the British Museum before also used the invisibility cloak, so the alarm system did not record a trace of image in the time and space of the suspect's crime, and the perpetrator is like invisible and untouchable air?" ”

"I also think it's the same gang." Cheng agrees, "Including the fact that there is no trace of broken glass, and the theft does not trigger any alarm system, all the methods are the same. ”

"But what I don't understand is why the infrared sensor alarm installed on the burglar window has not been damaged, and why the alarm signal is not emitted. It's the same with the British Museum, the alarm system doesn't give an alarm, which is too unbelievable, even if you put on an invisibility cloak, you can't do it. Chen Yufei asked.

"It can be done, for example, by using reflective metal thread fabrics, which are the materials used for firefighters' protective clothing, to be redesigned and worn on people's bodies, which can reduce the possibility of being detected by aerial surveillance tools, so as long as you wear 'invisibility clothing' made of special materials, it is not difficult to avoid infrared induction alarms." Cheng Yijie said, "When electromagnetic waves (including light waves) hit an object, they scatter on the object. When the scattered electromagnetic waves are received, it indicates that there is an object there. If electromagnetic waves can be allowed to 'turn' and walk around objects, so that objects can be 'invisible', the research carried out by Yang Ru's team is based on this concept. The core idea is that by modifying the refractive index of the material's surface, light can be 'turned' around the object and propagated in its original direction, so that the object can be hidden. ”

"When investigating Yang Ru's case, I also read a lot of relevant materials, including media reports." Chen Yufei took over, "Pendry, the proposer of the theoretical system of invisibility clothing, saw the research progress of Yang Ru's team, and he said in an interview with the British "Guardian" that this work is "a real progress" in the field of invisibility clothing research. In addition, in an interview with Nature, he further pointed out that everyone wants to have an invisibility cloak that can hide large objects in the real world in the visible light band, but to achieve this, some compromise design is required on the ideal stealth suit theory. He believes that Yang Ru's team has gone further than other researchers in this regard, and they have eliminated the condition that the transmitted wave phase requires consistency and realized a visible light stealth device with a considerable scale. However, from the perspective of application, if stealth wants to have a good application, it must be able to work in a wide frequency band, all directions, and all polarization, and it is very difficult to achieve this ultimate goal. The research of Yang Ru's team can only be effectively stealthy in several directions so far. ”

"Stealth can only be effectively achieved in a few directions, and that's the most critical issue." Cheng Yijie nodded and said, "That intruder must be very familiar with the layout of the corridor and the location of the surveillance camera, so he can be invisible in the picture throughout the whole process, so the possibility of insiders committing crimes is the greatest." ”

"Mu Qingcheng and Shi Qi are both very suspicious." Chen Yufei looked at Cheng Yijie, "I have to say that Mu Qingcheng's suspicion is the greatest, and she is the only one who took and returned the glass cabinet key from the smart key cabinet today."

Cheng Yijie disagreed. "If I were a thief, I wouldn't have gotten the keys until today, and I wouldn't have left a record."

Chen Yufei raised his eyebrows slightly. "Don't you trust her too much?"

"My woman, how can she be a criminal. I don't have even the most basic judgment. Cheng Yijie is full of confidence, "The key intelligent management system can control the key return management remotely through the Internet. The Conservation Office is open during business hours, and people inside the museum can come and go as they please. Anyone who can enter the office, even if they don't have identity authorization, can take the key with the help of a hacker, get another one, and put it back in its place, without leaving any records. As another point, the thieves entered the hallway at 7:45, almost 20 minutes before and after. I noticed that Qingcheng came on stage at exactly 7:45, how could she. ”

"What if two people work with each other?" Chen Yufei is still skeptical.

"The likelihood is basically zero." Cheng Yijie denied, "The more people know about this kind of thing, the easier it is to leak the news." There is already a chess piece like Li Dong for motivation, there is no need to pull another person in to increase the risk. I think that the person who poisoned and the person who dropped the bag were the same person. ”

Although Chen Yufei has always believed in Cheng Yijie's judgment, because of personal emotional factors, she couldn't completely dispel her suspicions about Mu Qingcheng, and only asked: "If according to you, when the thief entered the corridor, Shi Qi was also responsible for the transformation of props on the stage, then it could not be him." And Li Dong's girlfriend is not from inside the museum, that is, the three of them who are the most suspicious can be ruled out? ”

"It's too early to tell. At present, it is certain that the monitoring system and key intelligent management system of the exhibition hall have been hacked, and I need to know the specific time of the hacking. Cheng Yijie asked, "Please analyze it from your technical department and tell me the results tomorrow." ”

Chen Yufei agreed.

This night, Mu Qingcheng lost sleep again. There was such a mess in her mind, Cheng Yijie, He Muxuan, Gu Hengyu, the faces of the three of them were like close-ups on the screen in a movie, and they appeared in her mind in turn. Every face made her tired, but she couldn't sleep. Emotional distress, mental restlessness...... All kinds of things, she felt that she was involved in a big problem, and she became the core of the problem in a daze, and then created many new problems, which were like strands of entwined ramie, wrapping her layer by layer.

She tossed and turned in bed, unable to fall asleep, and began to count. From one count, to one thousand, I still have no sleep. As a last resort, she began to count backwards, and finally, her mind began to gradually become trance-like, and sleepiness slowly crept up her body, pressing heavily on her eyelids...... Then, in the dimness, she heard a knock at the door, as if someone had gently pushed it open and walked in. Her subconscious was still struggling with the numbers, the sound of footsteps, the sound of breathing, a shadow that seemed to be nothing, and a hand touching her face...... She jumped and sat up from the bed.

The light in the room was dim, she forgot to close the curtains, and the moonlight filtered through the glass windows, becoming a dull pale gray that filled the room. In front of her bed, a figure stood ghostly. It was a man, and the pictures in his memory suddenly overlapped, the uninvited guest on a rainy night in the duty room of the old glass factory, the man who threatened her to tell her the whereabouts of the USB flash drive, was also standing in front of her bed so gloomy and gloomy. He was wearing a trench coat, a hood, and a mask, the brim of the hood was pressed low, and his whole face was shrouded in darkness. Although she couldn't make out her face at all, she could feel that it was the same person as last time. I can't say why, she just has such a clear and strong feeling!

"It's you again!" She didn't know where she got the courage to shout out.

The other party seemed startled by her shout, and stared at him blankly.

She also looked at him fixedly, two flames of anger burned in her eyes, and the anger in her chest was also burning, even burning her fear and scruples. "Do you still suspect that the USB flash drive is here with me, I said it a long time ago, I don't know where the USB flash drive is, it's been so long, why don't you still let me go!"

The other party didn't say a word, didn't move, and his tall body stood upright. After the anger gradually subsided, Mu Qingcheng began to feel afraid, what did he want to do with her? Her heart was beating like a drum, and it was beating fast out of her throat.

Fortunately, after a brief standoff, the man suddenly turned around, strode towards the door of the dormitory, quickly opened the door, and slammed it shut.

There was a dead silence in the room, an oppressive silence. Mu Qingcheng wiped the cold sweat on his forehead, as if he had just woken up from a nightmare, everything was so vague and unreal. She lost the courage to be alone, and no matter what time it was, she grabbed her mobile phone with a trembling hand and dialed Yang Xirou's number. Unexpectedly, Yang Xirou answered the phone immediately, was she the same as her, sleepless in the middle of the night?

"Orange, what's wrong?" Yang Xirou's voice was very clear and there was no sleepiness.

"Cousin, can I go to you?" Mu Qingcheng muttered.

"Of course, come here." Yang Xirou said immediately.

Mu Qingcheng ran out of the dormitory in her pajamas, and Yang Xirou also lived in the dormitory of the Song and Dance Theater during this time, on the same floor as her. The corridor outside is darkly lit, looking up, the galaxy is about to dawn. There was a "squeak" sound in front of her, and Yang Xirou had opened the door and beckoned to her. She hurried over, and when she entered the house, she realized that her face was already covered with cold tears.

"What's wrong?" Yang Xirou asked with concern.

"I ......" Mu Qingcheng couldn't help but feel sad, his eyes were hot and humid, and he couldn't make a sound when he whimpered.

Yang Xirou gently stroked Mu Qingcheng's shoulders and waited for her to calm down. She herself was sad, and her beautiful eyes were full of sorrow.

Mu Qingcheng finally relented, at this moment, what she wanted to talk about most was not the uninvited guest, but the heavy blow and great distress brought to her by Cheng Yijie and He Muxuan. Cheng Yijie...... He...... He ......, "She couldn't speak, and under Yang Xirou's encouraging gaze, she finally sorted out her thoughts and told the truth that she was left out in the cold after she got married."

"You suspect that Cheng Yijie and that He Muxuan are ......" Yang Xirou's eyes were full of shock, "However, if there is a problem with his sexual orientation, you should be able to feel it before you get married." ”