The Nonexistent Thirteenth Door

One was a 2019 fire safety diagram. The other was the current facility diagram. The fold lines on the paper differed, but the red door numbers sat in the same places. From 1 to 12. The numbers stopped at twelve.

"We also requested the audit address list."

At my words, Han Dogyeong didn't push the third file forward with his fingertips. The file stayed tucked inside his elbow. A brown cover, half hidden, bore a label that read `2019_AUDIT_META`.

"The scope of the request is the diagrams."

"Because D-13 isn't on the diagrams."

Before he answered, he squared the corner of the desk twice. I couldn't yet tell whether it was a habit of aligning paper edges or a way of buying time.

Kang Taejun spoke from behind me.

"I read the file name. Why was that file excluded."

"The retention period is different. Audit metadata is bundled under separate access rights."

"Separate meaning it exists."

This time Han Dogyeong answered right away.

"The list exists. It's not an item that can be disclosed."

Every sentence carried a date and a clearance level attached to it. No person's name came up. I looked again at the diagram he'd laid out. Underground calibration room, medical office, generator room, records room. Twelve doors. Wall thickness and wiring box locations were marked too. There was no blank space for the number 13.

"Let's go to the site."

Kang Taejun didn't have me stand up first. He checked the restraint device on his wrist and left one security officer at the records room door. Han Dogyeong followed carrying only the two diagrams. The brown file stayed on the desk. Before closing the door, he put the file into a drawer. The drawer didn't lock. Like someone who knew an unlocked drawer stays in memory longer.

Before heading into the corridor, I flipped through the attached schedule under the diagram once more. The 2019 sheet listed the managing department beside each room name, while the current sheet listed the access card tier. Door 4 was security, door 7 was the audit zone, door 12 was the outer edge of the calibration room. The only thing that had changed between the two sheets was the department names. There was no trace of any added door number.

"Any expansions since 2019."

Han Dogyeong stopped folding the paper.

"None. If there had been an expansion, a completion record would exist."

"Have you seen the completion record yourself."

"It's in the archive room."

"Then let's check it."

This time he didn't object right away. Instead he spent four minutes pulling out the completion record file. He flipped through the index three times, opened the second drawer, then closed it. It could have been the motion of someone searching for an old document. It could also have been the motion of someone putting off an item they didn't want to find.

The completion record had an empty box for underground floor expansion approval. On the fire inspection sheet too, the maximum occupancy, evacuation distance, and number of fire doors were unchanged. Kang Taejun looked at the empty box and spoke.

"It's a record that proves something doesn't exist."

"Proving something doesn't exist is difficult," Han Dogyeong said.

"So we're going to look at a log that behaved as if it did exist."

13:10, the underground corridor felt shorter than the diagram suggested.

The feeling of shortness couldn't be trusted. We brought a tape measure. Kang Taejun walked from door 1. I matched the diagram's reference points against the actual wiring boxes. A fire extinguisher cabinet beside door 4, a drainage groove in front of door 6, an old CCTV camera above door 9. Everything matched the diagram. Past door 12 came a blocked wall.

Since Jeong Mugyeom hadn't joined us yet, we couldn't tear the wall open. It didn't seem necessary either. The paint on the wall showed the marks of a single coat applied on the same floor. There was a wiring inspection port, but it wasn't large enough for a person to pass through.

Kang Taejun knocked on the wall. The sound was dull.

"It's not an empty space."

"Then where did D-13 send power to."

"That question might be the wrong one."

I folded up the diagram. The question assumed a place. Where. But the generator log recorded an address, not a door. While we searched for a room number that wasn't on the diagram, we'd first assumed the log referenced the diagram.

Han Dogyeong spoke from the end of the corridor.

"D doesn't refer to a building on the diagram."

He said that much and shut his mouth. Kang Taejun immediately turned the question back on him.

"How do you know it doesn't."

"In 2019, the diagram's zone letters only went up to A, B, C. There was no D zone."

"Why did that information get left out earlier."

"No one asked."

Kang Taejun's gaze dropped to Han Dogyeong's hands. In his hands were only the two diagrams. No brown file.

We turned back at door 12. This time we walked the opposite direction. Counting from door 1, twelve. Counting from door 12, twelve. Elevator doors weren't included in the door numbering. Fire extinguisher cabinets, wiring boxes, and emergency stairwell doors were also excluded. Han Dogyeong stated the exclusion criteria precisely. So precisely that the same criteria could be used to hide something too.

"Are there any doors that open with exception authority."

Kang Taejun asked.

"It's not a door, it's authority."

Han Dogyeong corrected him right away.

"You know enough to correct that."

"I'm the records manager."

He added nothing after that. A thin line was drawn between what a records manager knows and what he hides. I thought that line resembled D-13. Not a physical space, but a slot that briefly opens only for someone with access.

14:00, back in the records room, Go Yura had the audit terminal screen open.

"It might not be a room number. It could be a mailing address."

As soon as she finished speaking, Go Yura corrected her own phrasing.

"More precisely, a data domain. Maybe the generator didn't actually supply power to a physical room. Maybe it found a ledger slot that had to record that power was supplied. The ledger slot's name is D-13."

"If it's a ledger slot, why did it only appear at 00:13."

"I don't know that yet. But if it's a room, the diagram is the reference. If it's a domain, the audit terminal is."

Han Dogyeong didn't stand in front of the audit terminal. He stopped between the drawer and the terminal. The distance was two steps. He could reach either one in a single motion.

"Would opening the 2019 metadata confirm this."

He raised his head at my question.

"It's an item that was frozen separately before the retention period expired. The reason for the freeze hasn't been disclosed."

"Who froze it."

"Only the account remains in the record."

"Did you see the account name."

This time Han Dogyeong didn't answer. Instead he pushed shut the drawer holding the brown file. The latch clicked. It was the same drawer that hadn't locked earlier.

Kang Taejun wrote it down. `Locked after being asked.`

He didn't say he suspected Han Dogyeong. He didn't need to say it.

Go Yura opened a new window beside the terminal. The domain list looked different from what appeared on a regular employee's screen. A, B, and C were linked to physical zones. D was empty. The empty row appeared last. The screen collapsed the blank field quickly, then expanded it again.

"This is a way of hiding a slot without authorization."

Go Yura said.

"Does a nonexistent slot look the same as a hidden slot on screen."

"To a regular user, yes. In the administrator log they should show up differently. Null if it doesn't exist, masked if it's hidden."

"In the chapter 10 log it was null."

"That's what's strange about it. There's no room, but power was sent. The address is null, but there's an active record. It's not that a package arrived at a house that doesn't exist. It's closer to the mail system creating a house that doesn't exist for thirteen seconds."

She finished speaking and seemed to feel her metaphor had run long, so she closed her mouth. Instead of the metaphor, Kang Taejun only wrote down the words. `null / active / 13 seconds.`

Han Dogyeong's gaze followed those three words. It paused once on "13 seconds" in particular.

"Did you already know that time."

I asked.

He didn't look at me.

"The audit procedure has a time window."

"What hour and minute."

"I can't disclose that."

"You just disclosed something equivalent."

Han Dogyeong checked his wristwatch. It was still afternoon. There was plenty of time before 00:13. And yet he already looked like someone who was running late.

23:59, four clocks stood in front of the audit terminal.

The central network's clock, Go Yura's independent tester, Kang Taejun's wristwatch, and an analog clock borrowed from the cafeteria. The central network was still 63 seconds slow. We waited for the date to change based on the independent tester, not the central network.

The Q-13 key hung around my neck. Kang Taejun had sealed the chain together with the wrist restraint device. It was a measure to keep me from pulling the key out and pressing it to the terminal.

"You said it could react even without touching it to the terminal."

"It has reacted before. It heated up."

"Heat and vibration are different."

"So we watch for both."

Han Dogyeong stood at the back of the records room. Go Yura recorded the terminal log. Kang Taejun watched the screen more than my hands. That was how the cooperation held together. Instead of trusting a person, we kept hands and screen in the same frame.

00:12:50.

Nothing happened.

00:12:57.

The central network's clock still showed the previous day. Go Yura counted the numbers, moving only her lips. I kept my hand open around the key. It didn't heat up. That made it stranger. Before, heat had always risen first when we got close to the core.

00:13:00.

An empty line appeared at the bottom of the terminal. The screen didn't open a new window. A single line slipped in beneath the existing audit list.

`D-13 / active / duration 00:00:13`

Go Yura drew in a breath and stopped herself. The motion of holding back any sound showed on the screen.

The Q-13 key trembled.

It wasn't heat. It came at a steady interval. Two short pulses, then one long. The rhythm came against my palm from the terminal's side, not from inside the wall. I didn't lift the key. Kang Taejun watched my wrist.

"Don't move."

"I'm not moving."

00:13:07.

The username field on the list flickered once. The letters had been erased, but a single stroke remained in the first slot. It looked like the first stroke of a Korean consonant, the line that comes before it becomes "Seo." Go Yura reached out to zoom in.

"Don't touch it," Kang Taejun said.

This time too, he didn't jump to conclusions. He chose to preserve the record instead.

00:13:13.

The count ended. The D-13 line disappeared. The wall stayed the same. The paint beside door 12, the wiring box, the blocked wall, none of it changed. No secret door opened. No underground floor appeared.

Han Dogyeong came up to the terminal for the first time. He only drew close after the screen had disappeared.

"You didn't find a room. You found a schedule."

Kang Taejun asked me. It was phrased as a question, but half of it was already an answer.

I set the key down on my palm. The metal had gone cold. There was no more vibration.

"Not a room. A slot that can open. Thirteen seconds past the thirteenth minute of every hour."

"Who goes into that slot."

I looked at the spot where the username had disappeared. The fact that there was no room wasn't the answer. If anything, it separated the door from the person. Without a physical handle, whoever had held the handle disappears too. What remained was only an account and a time.

Han Dogyeong spoke from behind me.

"Even if the account remains, that doesn't mean the person remains."

That sentence came too fast. Kang Taejun turned around immediately.

"Who said anything about a dead account."

Han Dogyeong shut his mouth. The unanswered question loomed larger than the new one. He had separated the account from the person before we'd even said the username belonged to someone dead.

Go Yura reached to rename the recording file and stopped her hand.

"I'll just leave the file name as D-13 active. No name guesses in it."

I nodded. If you put a guess into a file name, the next search returns the guess as if it were fact. Records outlive people. A lie that outlives people is worse.

Go Yura saved the recording file.

"Only the first letter is left. It's not a completed name."

"Don't complete it."

My words came out first. Go Yura looked at me.

"I mean let's not guess."

Kang Taejun wrote that sentence down too. Han Dogyeong wrote nothing. He stood like someone who'd emptied his hands so he wouldn't have to hear a name he already knew, said again.

00:13:14.

The terminal returned to its usual audit list. The diagram still showed only twelve doors. But the Q-13 key had trembled not in front of a place with no wall, but only in front of an address with no room.

There was no thirteenth door.

That made it clearer, not less.

If there was no door to find, there was no need to suspect a hidden handle either. Next time, all that mattered was watching who used that slot within those thirteen seconds.