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The person who called me was the Research Institute Internal Affairs Officer.

I understood that all the agents dispatched from the Information Agency were currently glued to the investigation, and that the dispatch team leader was in the investigation room as well.

“Here’s the report from the eavesdropping unit.”

“Thank you.”

The officer who handed me the documents left for a moment to attend to something, leaving me to read the papers in the meeting room. It was a familiar communication eavesdropping report.

Dawn.

Communication time: 9 minutes 51 seconds.

Two transmissions.

Approximately 500-character main text.

I flipped through the pages slowly, embedding a few keywords in my head.

As I confirmed whether there was any information that could assist in the investigation, a sigh escaped my lips as soon as I laid eyes on the content of the eavesdropped communication on the back page.

“Ha….”

The white background was densely covered with black numbers.

“…Now even industrial spies are using codes.”

It was an encrypted communication report.

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Episode 3 – Fantastic Vacation

The military and information agencies use codes to exchange critical communications.

In preparation for the possibility of communication being intercepted, the contents are encrypted so that they cannot be comprehended.

Password phrases and call signs are, in a way, primitive forms of encryption. It’s because only we know the meaning of those words.

In that sense, the message dispatched by the industrial spy could be seen as a text encrypted with numbers.

“This looks like a random number table no matter how I see it….”

Random number table.

An encoding system that links numbers to words.

001 – Return. 101 – Command.

With codes designated like this, if ‘001 101’ is transmitted via random messaging, the listening spy deciphers the code to receive the instruction “Return Command.”

This is a well-established encoding system that has been widely used from World War II to the Cold War, and is a beloved encryption method of the military and information agencies, as it is impossible to decrypt without the random number table.

In fact, even without the random number table, one could easily create a code with just two ordinary books. If the page number and line number are provided from the random broadcast, one could take the first letters of the corresponding sentences.

My grandfather, a former Central Intelligence Agency Inquisitor, said that the North Koreans often used this method. We used it frequently too.

Anyway.

The problem is that deciphering this is extremely difficult.

I sat on the meeting room chair, lost in thought for quite a while.

“Oh, you were here early.”

“…Team Leader.”

“I’m sorry, the investigation got slightly delayed.”

“No, it’s fine.”

Suddenly, the door opened and a person in military uniform entered. It was the team leader dispatched from the Information Agency.

I handed the read report to the team leader, who had settled into a chair across from me.

“Is this the data from the eavesdropping unit?”

“Yes, please have a look.”

He took off his glasses from his pocket and started reading the report. His expression began to sour in real-time.

“…It’s an encryption using a random number table.”

True to his role as a counterintelligence agent, the team leader pierced through the encryption used in the report. He let out a faint sigh and rubbed his weary eyelids after taking off his glasses.

I offered him a bottle of water to break the ice of our conversation.

“I also think it looks like a random number table code. Encoding with numbers is pretty standard for that.”

“If this is a one-time code, it will be impossible to decipher.”

He continued, narrowing his brow. His expression was very serious.

“We’ll match the data against the encoding systems we’ve collected so far, but if this code is new, it might take months to decipher.”

“Decrypting codes is inherently complicated and challenging, isn’t it?”

From what I heard from my professor in a past life, code creation and decryption tasks typically require a large number of linguists and mathematicians.

For instance, there’s a story about how the British intelligence agency formed a dedicated team to crack the Nazis’ Enigma during World War II. They eventually succeeded in breaking the code.

“How’s the investigation going?”

“Yes. Progress is smooth because the number of suspects has decreased.”

“That’s good news.”

We killed some time exchanging brief work-related conversations, as we were waiting for the absent internal affairs officer to return for the meeting.

“I feel like no matter how much coffee I drink, it doesn’t help.”

“Don’t drink too much. If you keep staying up and drinking coffee, it’ll be bad for your health.”

“I think I might need to visit the hospital since my chest has been tightening lately. How about you, Colonel?”

“Oh, I’m still holding on just fine.”

I forced a smile while rubbing my bloodshot eyes. Sitting there for too long was starting to make me restless, so I picked up a water bottle and started pacing around the room.

When I get leave, I should either visit the hospital or seek out a healing priest. I need to ask Lucia for a healing when she arrives.

“…By the way, something feels odd.”

The team leader murmured ambiguously while peering at the report.

“Yes? What seems odd?”

“There’s no reason for an industrial spy to use an encrypted message.”

Hmm?

Thinking back, something seemed strange.

“I understand that operatives typically meet with information agents only at predetermined locations.”

“…That’s right.”

“Spies generally condense the message and send a brief communication report, saving the detailed accounting for after returning to their home country.”

“….”

“However, the industrial spy transmitted a message of around 500 characters twice over 9 minutes. They even used Morse code.”

As I unscrewed the water bottle, I quietly mulled over the team leader’s words.

The means of communication in this world are similar to that of modern-day.

To be precise, the long-distance communication methods are akin to modern technology. For short distances, simple magic suffices, but to communicate across borders, scientific technology is essential.

The only difference is that instead of radio waves, they utilize magic wave frequencies.

“The employees of the research institute can go out freely and take leaves, right?”

“I believe outings or leave require the director’s approval, not vacations.”

They can’t just go out at will.

“Then it seems impossible to meet operatives casually.”

Hmm.

“So, it means the only way to contact them is through communication….”

“That would be impossible. I believe the internal affairs department monitors and records calls as per security protocol.”

If it’s logged in the network, communication reports are impossible to make.

“Then the only option left for the employees here to communicate with the outside is long-distance communication.”

Taking a sip of water, I fell into contemplation.

What is the representative long-distance communication method in this world? It’s none other than the radio. Not the kind that exchanges voice communication, but one that sends and receives signals resembling Morse code.

“Can magic waves be transmitted beyond this valley?”

“If there’s sufficient output, theoretically, communication is possible from anywhere. Even if the sensitivity decreases, if the wave hits the receiver, you can definitely communicate.”

Using Morse code for communication, huh.

By modern standards, Morse code is a technology that has been around for over 150 years.

However, it is a fundamental technology that has been widely used from World War I through the Cold War to modern times, and it remains a beloved communication method for the military and information agencies because even if base stations or satellites fail, communication is still possible.

That’s why it is often used by special forces and spies infiltrating deep into enemy lines. The special ops communication specialists who carry radios on their knees are a typical example.

However, Morse code has a critical flaw.

First, it requires considerable effort to learn and master Morse code. The sounds of Morse code are difficult to comprehend, and sending it accurately takes a significant amount of know-how.

It also involves risks like enemy communication interference, disguised communication, triangulation-based location tracking, changes in solar spots, solar winds, and Earth’s magnetic field fluctuations—all manner of hazards loom.

Morse code is a jumbled mix of agonizing flaws and advantages, a love-hate relationship in communication technology.

“Surely, the research institute staff would be well aware of the security protocols, and do they know about the presence of the eavesdropping unit nearby?”

“The exact location of the communications eavesdropping unit is military confidential.”

“They probably don’t know.”

The biggest issue in communication is interlopers intercepting signals.

With enough transmitters, triangulation can precisely locate the source of the signal.

My grandfather, who was an intelligence officer, said that even during the 70s, North Korean spies were often caught while reporting over the radio.

Naturally, the military and intelligence agencies in this world are aware of this as well.

“The industrial spy communicated for 9 minutes.”

“Yes.”

“Is it possible to transmit a 500-character message twice within 9 minutes?”

“I believe a skilled radio operator can send about 100 characters per minute. It’s certainly not impossible.”

The industrial spy infiltrating the research institute attempted communication using Morse code. Given that if there’s sufficient output, communication is possible from anywhere, it’s understandable behavior.

This level of information would be common knowledge for a scientist or magician with a degree. There’s nothing strange about it.

But the industrial spy transmitted a message of around 500 characters twice within 9 minutes.

While trained people in the military and intelligence agencies can handle 100 characters in a single minute, an ordinary researcher manages to send 1000 characters in 9 minutes? That doesn’t add up.

He could be someone with a hobby in amateur radio, but even in modern times, that’s a pretty niche hobby. While one might learn Morse code online today, in this world, it’s virtually impossible for a civilian to acquire Morse code knowledge and communication skills.

And considering that industrial spies are typically infiltrated civilians, they are far from regular military training.

Therefore, the transmitted communication from the research institute cannot be considered the work of a civilian.

Moreover, the message was transmitted encrypted with what is presumed to be a random number table.

What that means is.

“…Shit, this guy is a spy.”

This means he’s not just a run-of-the-mill industrial spy who was just paid off; he’s a formally trained spy.

There is a spy in the research institute.

 

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