Chapter 4

"Allow me to introduce these two individuals—Agents Xu Lian and Selina Myers from the Federal Bureau of Investigation," the Director said to Li Chi and Sun Yuan. The two seated on the sofa immediately stood and extended their hands for a handshake. The first was an Asian man, robust in build, with unmistakable mix features; the other, a tall Caucasian woman with blonde hair. Both were dressed in well-fitted, dark blue suits, a stark contrast to Li Chi and Sun Yuan's programmer-style windbreakers and checkered shirts.

"I'm Xu Lian, FBI Agent from the Cyber Crimes Division's International Liaison Office. It's a pleasure to meet you," the man with a typical Asian accent introduced himself.

"Li Chi, Captain of the Cyber Crime Investigation Unit, Ninth Division, Beijing Public Security Bureau." Li Chi quickly responded, shaking his hand.

"Selina Myers, FBI Agent, Cyber Crimes Division's International Liaison Office. It's a pleasure to meet you." Li Chi was surprised that the Caucasian woman could speak fairly fluent Chinese, though her accent was peculiar. They exchanged formal greetings for a moment.

The next morning, Li Chi and Sun Yuan arrived at the office, intending to make some brief preparations before heading to the location they had pinpointed the previous night. However, the Director called them into his office. Li Chi hadn't expected to find two A' country waiting for them.

"I won't waste any time here. Mr. Xu and Ms. Myers will assist you in investigating Zhou Tao's cybercrime case. This is a directive from higher authorities," the Director emphasized the words "higher authorities" with particular weight. "I'll leave it to our A' country colleagues to explain the specifics."

"We are here for the Zhou Tao cybercrime case." After some pleasantries, they found a conference room where Xu Lian connected his laptop and began the presentation. "We have reason to believe he is connected to the recent theft of a quantum processor from the Alphabet Quantum AI Lab."

Li Chi noticed that Sun Yuan's expression grew increasingly serious. The Director, seated at the back, remained impassive.

"About eight weeks ago, the Alphabet Quantum AI Lab reported to the FBI that their most advanced quantum processor, still in the experimental stage, had been stolen. No clues were left at the scene; it was almost a perfect crime. We suspect it was an inside job." Projected on the screen were photos of the lab, neat and orderly, resembling any typical university laboratory. An arrow marked the spot where the quantum processor had been. It was roughly the size of the processor box they had seen at Peking University, but empty. Aside from this, the lab was immaculate, with no signs of intrusion—except for the traces left by FBI agents.

"We encountered significant challenges during the investigation. We scrutinized all personnel with access to the lab, but they were all cleared of suspicion. Eventually, we resorted to large-scale deep learning techniques, categorizing those who could have entered the lab. The conclusion pointed to Mr. Zhou Tao. He visited the U.S. eight weeks ago and stayed near the lab for forty-eight hours before returning to China. Our investigation revealed that his luggage increased by approximately twelve kilograms upon his return, matching the weight of the processor." Xu Lian displayed a series of images captured by the Quantum AI Lab's surveillance cameras. The man in the footage indeed resembled Zhou Tao. The timestamps were just before and after the processor was stolen.

"We have no record of Zhou Tao ever leaving the country. Even if he was near the lab, how did he manage to enter and acquire the quantum processor?" Sun Yuan's voice emerged from behind, tinged with a cold undertone.

"He erased his records from the Immigration Bureau's database, which is possible. As for how he entered the lab, we haven't determined that yet. The surveillance footage from the lab was deleted at the time and is unrecoverable. Gentlemen, considering the series of events that unfolded after Zhou Tao returned to China, I am convinced he is the suspect who stole the processor." Xu Lian looked around, raising his hand to clarify.

"Even if he did steal the processor, could he have simply brought it back to China on a plane?" Sun Yuan pressed on.

"As for that question," Xu Lian responded, "the following photos must remain confidential." Displayed on the screen was a glass box, resembling the one they had seen at the Peking University lab, though this one was slightly rectangular.

"This is the appearance of the Alphabet Lab's quantum processor. I see none of you are particularly surprised." He glanced around the room, as if realizing something. Li Chi felt a sinking feeling in his chest.

"Given the circumstances, it would be feasible to disguise the processor slightly and pass it off as an art piece when boarding a plane." Xu Lian continued, as if nothing had happened. Li Chi glanced at Sun Yuan, whose face, illuminated by the projection, was tense, his lips tightly pressed together.

"We later discovered some anomalies in the network traffic. Several major internet companies reported they had been subjected to perfect man-in-the-middle attacks. Eventually, we traced the source of these attacks to Zhou Tao. And so, gentlemen, we are here." Xu Lian flipped to the last slide, showing a joint directive issued by the Ministry of Public Security and the Ministry of Foreign Affairs, instructing the Beijing Public Security Bureau to provide necessary cooperation and assistance to the FBI's Zhou Tao Task Force and to form a joint task force when appropriate.

At this moment, Selina, who had remained silent, stood up and walked over to Xu Lian. Clearing her throat, she said, "Cybercrime has always been a high-risk area for transnational offenses, but we have never encountered one of such high technical sophistication. This incident has even alarmed the President, who is deeply concerned about the potential repercussions of such an advanced technology being stolen. We are grateful to your government for making this joint task force possible."

Xu Lian sat motionless, while Li Chi surmised that Selina was the true leader. The presentation concluded.

"Thank you both for the report. Let's not waste any more time," the Director said as he stood up, addressing the four of them. "Given that Li Chi and Sun Yuan are the lead investigators on the Zhou Tao case, I hereby establish this joint task force with the four of you. Mr. Xu and Ms. Myers, we highly regard this advanced technology crime case involving Zhou Tao. You have full access to all related materials, and for specific details, you may consult Captain Li Chi. I authorize him in this matter." The Director finished speaking with an impassive expression, casting a glance at Li Chi. He then hurriedly left the room, as if avoiding something.

"Captain Li, do you have anything to add?" Xu Lian asked, looking toward Li Chi. Sun Yuan's expression was grim.

"We have an old saying in China: 'Hearing a hundred times is not as good as seeing once.'" Li Chi smiled. "We obtained a new lead just yesterday, and before you arrived, we were planning to investigate it. Rather than sitting here idly, why don't we visit the site together?"

"Agreed." Li Chi parked the car. They had arrived at an old residential complex outside the Third Ring Road. As the city developed, these neighborhoods gradually transitioned from upscale residences to ordinary housing. With the advent of autonomous driving, the underground garages had been converted into various small shops, leaving Li Chi to park at the entrance. Throughout the drive, Xu Lian and Selina sat in the back, silently engrossed in their phones, while the usually talkative Sun Yuan remained tight-lipped. They reached the location in silence.

The four of them exited the car without a word. Sun Yuan couldn't help but glance back at Xu Lian and Selina's attire—their formal suits stood out in the setting.

"Is this where Zhou Tao is currently located?" Selina asked.

"We suspect this place may hold clues," Sun Yuan responded on behalf of Li Chi, checking his phone. "Our initial assessment points to this complex. According to the collected tenant information, three apartments are particularly suspicious: Building 1, Apartment 1307; Building 4, Apartment 604; and Building 9, Apartment 2002."

"Captain Li, what exactly are we searching for?" Xu Lian inquired.

Li Chi glanced at Sun Yuan, signaling him to answer. Sun Yuan typically handled such technical details. "Recently, we traced the use of liquid helium for cooling to this location. Spatial data analysis indicates that these three apartments were originally vacant but have shown recent water and electricity usage. Surveillance footage is unreliable since the suspect could tamper with it, but the utility consumption can't be hidden. Did you bring temporary police IDs? Excellent. Should we split up or search one building at a time?"

"Captain Li, let's split up. We'll head to Building 4 and regroup at Building 9," Selina hesitated before replying.

"Let's move." Li Chi called for Sun Yuan, and the four of them passed through the gate, dividing into two teams to head toward their designated locations.