The fairy maid cheers for her deceased master today.

Elena took the magical detector out and brought it back to the ground to show everyone.

At this moment, she exclaimed that Angel had such a keen eye, often noticing these differences. Angel chuckled shyly at this.

Then Angel stood on tiptoe and stared curiously at the small box: "Master, the surface of this thing seems to have been scratched."

Officer James immediately came over and found that it was indeed the case.

Ax shook his head: "The serial number and manufacturer's logo have been erased; the criminal is very cautious."

He paused, a sharp glint in his eyes. "However, each workshop's detectors have unique technical characteristics. We can find potential buyers by analyzing their manufacturing process and material composition."

After all, Ax himself works in this industry, so he has a basic understanding of it.

Although X doesn't understand magic, he does understand manufacturing processes and materials.

James rubbed his hands excitedly: "Just like a detective! Finding the truth through details! What are we waiting for?"

Axe gestured for the officer to calm down, then smiled slightly and began to carefully examine the detector.

The welding marks on the edges of this tiny detector are so fine that the seams are almost invisible, demonstrating the maker's exceptional skill. The detector is made of a special copper alloy with a specially treated surface that gives it a unique dark golden luster.

Based on Axe's experience, the world today can only handle large, bulky components. For delicate metal boxes the size of a fingernail, neither the welding precision, heat source control, nor materials technology allows for their development.

In short, such delicate welding would be impossible to accomplish without magical assistance.

There must be fairies in the mechanical workshop that makes this kind of magical detector.

"Look here..." Ex pointed to the marks on the edge of the detector. "Only a few workshops can do this kind of welding, and it requires the assistance of fairies. And this alloy... I remember seeing a similar description in the 'Mechanical Engineering Weekly'."

Angel asked curiously, "Then how do we find out which workshop made it?"

AX chuckled and said, "It's simple, just ask."

"Oh...huh!?" Angel blinked.

X gently patted Angel's head.

"We already have magic detectors, so we can just take them over and ask. The craftsmen in our own workshop shouldn't be able to mistake our work."

He stood up, dusting off his hands. "Let's go visit the workshop that sells magic detectors. They probably don't have many, right?"

■

Such machine workshops are indeed rare.

James quickly returned to the Royal Magical Society and used his police powers to obtain a list of mechanical workshops that were cooperating in selling magical detectors.

Next, we visited each family one by one.

The first workshop had a copper signboard hanging at the entrance, with the words "Starry Sky Workshop" engraved on it.

"Wow, Master, look, the name of this mechanical workshop is so nice!"

Angel stood on tiptoe, pointing at the glittering sign, her blue eyes full of curiosity.

"Not as good as ours." Elena, of course, felt that the name she had chosen was better.

Ex gently knocked on the door, and an elderly mechanic wearing glasses and an elf assistant opened it to greet him. The old mechanic carefully examined the magical detector, then shook his head:

"It's not our process; our welds are more rounded."

The second workshop was located in a narrow alley, the air thick with a mixture of metallic and magical scents. The young mechanic took the detector and carefully examined its edges with a magnifying glass:

"The material is very similar, but our products all have unique serial numbers, while this one has nothing on it."

"Wasn't it erased?"

"Haha, don't worry. Our craftsmanship won't just disappear by erasing it. It's a hidden serial number."

The third and fourth workshops also gave negative answers. Angel's little face gradually fell, and her blue eyes were filled with disappointment.

"Don't worry, we still have three more." Ax gently ruffled her hair.

The fifth workshop, located in central London, is a high-end-looking shop with a sign that reads "Royal Precision Machinery" at the entrance. The decor here is more refined than the previous shops, with display cases showcasing various exquisite mechanical products.

A well-dressed gentleman greeted them. His eyes lit up when he saw the detector.

"This...this is very likely our product." He examined it carefully. "Look at the welding process, and the external characteristics of this alloy; they all meet our standards. However..."

"But what?" James asked eagerly.

"However, we and two other workshops have recently obtained patents for this technology, so it could also be their product," the gentleman explained. "It's a latest patented technology, and all three of us manufacture strictly according to the patent standards."

Angel asked curiously, "Then why do the three workshops make exactly the same things? If they share the same patent, do they also need to use the same manufacturing methods?"

"Because this is a strict requirement of the patent," Elena explained. "The manufacturing process of the magic detector is extremely precise, especially its internal structure. Each workshop must manufacture it according to the exact same blueprints and material formulas to ensure the accuracy and reliability of the detector."

In other words, extremely strict patent restrictions have led to the disappearance of the distinction between different workshops.

James frowned. "Is there any way to determine exactly which company made this device?"

The gentleman shrugged: "It's really hard to say. All three of us use the same materials and processes, and our products are almost identical."

Seeing that the other fairies and humans were also distressed.

AX immediately laughed: "There are only three left. Same as always, just ask directly."

"What do you want to ask?"

"Of course, we should ask who has bought this thing."

When in doubt, just ask!

A brute-force approach will suffice.

These words made James realize something.

He immediately adopted the demeanor of a police officer and asked the gentleman, "Have any fairies recently purchased magic detectors?"

"A fairy? That's way too wide..."

James tapped his head: "No, no, I meant this guy."

He immediately took out a black and white photograph of Lucy and handed it to the gentleman.

The gentleman examined the photo carefully and shook his head: "I've never seen this fairy before, or rather, I have no recollection of her."

Great, another one has been eliminated.

But soon, Ax realized that he had been thinking too simply.

Because the sixth and seventh workshops gave the same answer.

They all said they had never seen this fairy before.

As Angel emerged from the last workshop, her lips were pouting, and her blue eyes gleamed with confusion.

"Could this magic detector have been stolen?" Angel tilted her head and muttered softly.

Even James put his hands behind his head, looking completely bewildered.

"What's going on? What's going on? No fairies have come to buy it, but there are no records of thefts from these mechanical workshops either. Can this magical detector be created out of thin air?"

As X walked, he kept looking down at the magic detector.

If Lucy didn't buy it, then who else would need it?

According to Elena, this can be used to monitor the state of the barrier... wait!

No way.

But this is also one of the possibilities.

So he had the others follow him to visit the three workshops again.

This time, Ax presented a black and white photograph of Caroline.

"Have you seen this fairy? Has she recently purchased a magic detector?"

The first workshop owner shook his head, and the second shook his head as well. When Ex arrived at the third workshop—the gentleman's workshop—the gentleman's eyes suddenly lit up.

"Ah! I remember now!" He pointed to the photo. "It's her! This fairy lady came to buy a magic detector a week ago!"

It turns out... it really was Caroline who bought it!