I started with a ship full of max-level veterans, and I'm just a complete noob.

The crew-cut clerk ran ahead, with Jiang Ming following behind. The two crossed the dirt road between the workshops, their shoes sinking into puddles after the rain, not caring about the water splashing onto their trousers.

Only half of the streetlights in the factory area were lit, the rest were completely dark. In the distance, from the direction of the south gate sentry post, there were flashlight beams flickering, and someone was shouting something, the sound broken and intermittent by the wind.

When Jiang Ming ran to the south gate, he first saw Director Wang standing under the porch of the guardhouse. His military overcoat was unbuttoned, one hand was in his pocket, and the other hand held a cigarette, the red dot of which was flashing on and off.

A person was lying on the ground with his arms tied behind his back, held down by two soldiers brought by the crew-cut officer on his left and right.

The man was wearing a dark blue cotton-padded jacket worn by postal workers. His back was covered in mud, his hat had fallen off, revealing his very short hair. His face was pressed against the ground, and his lips were trembling.

A military green canvas parcel was hanging on the barbed wire fence next to it, with one of the straps broken off, indicating that it had been torn off.

When Director Wang saw Jiang Ming approaching, he stubbed out his cigarette and stepped on it, then gestured with his chin toward the mailbag.

"See for yourself."

The flat-topped clerk had already opened the package; the contents were spread out on the wooden table in the reception room, brightly lit by the incandescent bulbs.

Three ordinary letters, a mailing register, a fountain pen, and half a piece of sorghum candy.

There was also a kraft paper envelope with a red top-secret registered mail stamp affixed to the upper right corner. The recipient address was written as the Gansu Office of the Material Allocation Department, and the handwriting was neat and in blue ink.

The envelope had already been opened by Director Wang, and inside was only a folded light blue notepad.

Jiang Ming leaned closer to look at the paper. Under the light, the paper was covered with tiny characters written with a very fine dip pen tip, barely legible to the naked eye.

The first line reads: Yuanlei No. 1, frequency 2.952GHz.

Second line: Anode voltage 12000V, magnetic field 0.15T.

Third row: Cerium oxide electrophoretic deposition at the cathode, coating thickness 60 micrometers, deposition voltage 80V, time 12 minutes.

Fourth line: Anode material is domestic oxygen-free copper, eight-cavity structure, machined by eccentric turning.

Fifth line: After the first ignition, the frequency drift is less than five parts per million for 30 minutes of continuous operation.

Jiang Ming's back was completely soaked at that moment, not by rain, but by sweat.

These data were recorded on the test report just three hours earlier.

The inspection report was locked in a safe in a secure compartment, and only he and Wu Hanzhang had the key.

But every number written on this blue paper is exactly the same as the one he recorded.

He took a step back, his fingers gripping the seam of his trousers, and said nothing.

Director Wang walked over and stood next to him, his voice very low.

"Two hours ago, this letter was stuffed into the internal mailbag of the material allocation department, and was instructed to be sent out overnight through the confidential mail channel. The recipient address was the Gansu office, but the person in charge listed in the mailbag registration column was Li Huaiyuan's secretary."

Jiang Ming turned to look at the postman lying on the ground.

"How was he arrested?"

The crew-cut officer interrupted, his voice still carrying the lingering heaves from chasing someone.

"At 10:30 tonight, the people I arranged to keep an eye on the south gate saw this person ride a bicycle from the east side of the factory area to the base of the wall. He didn't go through the main gate or the guardhouse, but climbed over the wall directly. The package contained this letter."

"A postal deliveryman, sneaking into the factory in the middle of the night to deliver confidential documents." Director Wang stuffed the half-smoked pack of cigarettes back into his pocket. "Do you think that's normal?"

Jiang Ming did not answer the question; his attention returned to the blue paper.

A short, red, very thin fiber, less than a centimeter long, was stuck in the crease of the paper, and it had a slightly fuzzy feel under the light.

He didn't touch it, he just squatted down and took a look.

It's made of wool, not cotton, and not synthetic fibers.

In this day and age, not many people can afford to wear woolen coats.

Director Wang clearly noticed the fiber as well. He picked it up with tweezers, put it in a glass medicine bottle, tightened the cap, and put it in his pocket.

The deliveryman on the ground started crying; his voice was unpleasant, filled with snot and the smell of dirt.

"I don't know what's written inside, I really don't know. Someone just asked me to deliver it and gave me five yuan."

Director Wang squatted down in front of him.

"Who is it?"

"The person from the materials allocation department said he was Li Huaiyuan's secretary. He was in his thirties, wore glasses, and was dressed in a gray Zhongshan suit. Two hours ago, he handed me the letter outside the Dongzhimen Post Office and told me that I had to deliver it to the factory's confidential office tonight. He said I had to leave for delivery first thing tomorrow morning."

"Why didn't you use the main entrance?"

The deliveryman stopped crying for a moment, then turned his face away from the ground.

He said there's a registration system at the main entrance, but this letter doesn't need to be registered; just put it in the mailbox in the confidential room.

Director Wang stood up and patted the dirt off his knees.

There were no cars on the road outside the South Gate; only the wind rustled the tree branches, and dogs barked in the distance.

He walked over to Jiang Ming, took the medicine bottle containing red fibers out of his pocket, looked at it under the light, and then put it back.

"Only the few people in your cubicle knew the ignition time of Yuanlei-1 this afternoon," Director Wang said softly, as if confirming with himself. "But this letter was written two hours ago, which means the writer obtained all the parameters less than an hour after your successful ignition."

Jiang Ming didn't reply; he was thinking about something.

The inspection report was locked in the safe, but he was present during the ignition process, as were Fang Xudong, Lao Sun, Xiao Zhao, and Da Liu.

Five people.

Of the five people, none of them left the secure compartment. From the moment the fire was lit until the flat-headed clerk rushed in to tell him to go to the south gate, no more than forty minutes had passed.

So how are the parameters transmitted?

Director Wang seemed to see right through him and shook his head.

"It might not be someone in your cubicle. It could be someone who saw something during their three-day shift at the exhaust station. It could also be that someone has been watching the cathodic electrophoresis formula for a while now. Or it could be that someone peeked at the frequency meter readings from outside the observation window this afternoon."

He paused for a moment and buttoned up one of the buttons on his military overcoat.

"But one thing is certain: Li Huaiyuan was arrested the night before last. The fact that his secretary dared to come out and deliver a letter today shows that the person in charge of this matter was not Li Huaiyuan."

Director Wang collected the blue paper and envelopes from the table, put them into a tin document box, and locked the box.

He turned around and stared at Jiang Ming's face for two seconds.

"Old Lei's case back then was also leaked in this way."

Jiang Ming felt a chill run down his spine upon hearing the name.

Director Wang had never brought up Lao Lei's case in front of him before.

"Let's go." Director Wang tucked the briefcase under his arm and walked towards the jeep parked by the roadside. "Interrogate Li Huaiyuan tonight; we must get the real name of this messenger."