5:44

"It's ringing again."

After closing time, Dania emerged from the back room holding a recording terminal; the screen displayed a brand-new waveform. "Three o'clock in the afternoon, when the store was empty. This time it's a full eleven seconds, not a single second missing."

The long table was cleared out, and the analysis was set up. Sigelica was taking apart and putting back together the first aid kit, unable to get involved, and was pacing around anxiously. Chisa wiped the knife for the third time. Bozai was leaning over the corner of the table supervising, his tail idly stroking the tablet. Chisaki laid out the three recordings side by side, the new and old ones, plus the earliest one, their waveforms almost overlapping.

"Still the same problem," she said. "Eleven seconds, like a sentence, only half-finished."

"Then let's complete the sentence," Zhou Yu said.

Chisaki's finger paused on the screen for a moment, then she dragged the new recording into the rewind bar and pressed run.

A stream of noise emerged. This time, it was no longer just noise.

In the reversed waveform, a lingering sound emerges first, followed by the chime of a bell. One chime after another, steady and slow, striking a full eleven times. At the end of the chime, a half-sentence of human voice hangs out, drawn out and indistinct, with only the last two words barely legible.

Care.

The shop remained quiet for a long time.

"I heard that every day when I was a kid," Chisaki said, her voice lower than usual. "Old Honami Morning Voice airs every morning at 5:44. The opening sequence is eleven chimes, and the closing line is just one sentence: 'Nice to see you again on this new day.'"

"The elderly on the early shift follow it to buy groceries, and children follow it to school." She paused, "Only after saying that did the whole city truly wake up."

"So that background noise was played backwards?" Sigelica asked.

"A reversed closing, a bell ringing backwards." Chisaki superimposed the two waveforms, "It's playing backwards. Not a single episode missed."

"Who broadcasts this backwards?" Sigelica scratched her head.

"Wait until you finish speaking," Chisa said, wiping her knife.

Dania listened to the chimes again, tilting her head.

"If it's knocking backwards, people won't understand it," she said. "Is it knocking for itself to hear?"

Chisaki glanced at her and typed the sentence into the notes section.

Chisaki didn't stop. She overlaid this reversed spectrum with three old files: the readings from the Black Stone Memory Stone, the curve of the Tethys Dark Spot, and the remnants of Aleph One. The three lines overlapped almost completely on the last layer.

"Same origin," she said. "All of them are of the same origin."

"The same machine?" Zhou Yu asked.

"It's not a machine, it's from the same source." Chisaki shook her head. "It's not copying their homework. It's the teacher."

"And what about the student?" Sigelica asked. "Who is the student?"

"I don't know," Chisaki said, "But the homework was handed in in this city."

The tablet screen went dark, revealing Chisaki's face. Dania suddenly remembered something and turned around.

"Chisaki."

"Um."

"Last time on the Black Shores, Chengxia stayed there. Why didn't you go see her?"

The shop fell silent for a moment. Chisa stopped wiping her knife, Sigelica went to look at Zhou Yu.

"I went," Chisaki said. "The day I finished checking the logs, I stood downstairs at her place for a while. The lights upstairs were on."

"And then?" Sigelica asked.

"Then I came back." Chisaki flipped her phone face down on the table. "I need to say something when I come in. I haven't thought of what to say yet."

Zhou Yu didn't reply. He opened the schedule and added a line at the end of the page with Chisaki: Listen to it, then knock on the door. The store will reimburse your travel expenses.

Chisaki stared at the words for two seconds, then turned the tablet back on, screen facing outwards, and placed it back in the center of the long table.

"Let's hear about that first," she said. "Knocking on the door can come later."

As soon as he finished speaking, a notification sound came from the canvas bag.

The old-fashioned digital watch lit up by itself for the first time. No one touched it; it automatically popped up a new notification, scrolling up line by line.

[Same-source frequency confirmed: not Aleph One. Origin: local. Era: early.]

"Good morning, how good is it?" Sigelica leaned closer and read.

No one could answer that.

"Aleph One on the Black Shores, and so is Tethys." Chisaki looked at the superimposed spectrum, her voice softening, "It says 'local,' and it's the only one on the entire table."

Zhou Yu took out the digital watch, stared at the word "early" for a long time, and didn't say anything. Inside the canvas bag, the memory stone, separated by the cloth, felt a little warmer than usual.

In the middle of the night, Zhou Yu took Dania to the Rainbow Sound Tower.

The check-in area was on the first floor, and the windows were lit. The check-in clerk was a young man with dark circles under his eyes, even darker than the lights. He sighed when he saw the two people standing at the door.

"Those guys who did the good deed, right?" He opened the door. "The registrar greeted you and said you were coming. He told you to look around, but not to touch anything."

"He's quite generous," Zhou Yu said.

"He said to stop checking, but yesterday he went through all three of your files." The check-in clerk pushed two cups of hot water towards us. "Ask whatever you want. That's all I know anyway."

"Why are you telling us?" Zhou Yu asked.

"Last time, that huge thing on the main street was reduced to ashes, not a single spark landed on the stalls next door," the check-in clerk said. "I watched the replay three times. You guys fight cleaner than I change a fuse."

"The old archive," Zhou Yu said.

"It's running on its own," the operator whispered. "Recently, every two or three days, there's been a load in the early morning. The meter shows power, but the access control records are blank. There's only one key to that room in the whole tower, locked in my drawer, and I've never lent it out. Whether anyone's been in there, God knows."

Have you reported it for repair?

"Reported. The higher-ups approved four words: 'Pending observation.'" The check-in clerk gave a wry smile, "The same treatment as your 'pending' situation."

Dania held the hot water in her hands and asked softly, "What's in there?"

"An old broadcast control console, an old cassette tape, and an old transmitter connected to the main antenna." The operator paused, then became serious, holding up one finger. "Remember this: if you really need to go in, don't touch the broadcast button. That system is live; once it's connected, the whole city can hear it."

"So what if I heard it?" Dania said.

The check-in clerk was taken aback.

"It just wanted to finish what it was saying," she said earnestly, finishing her water. "It'll be fine once it's done."

The check-in clerk didn't respond. He looked at her for a moment, his dark circles under his eyes, then took the key out of the drawer, put it back, and locked it.

"If you really want to come," he said, "Let me know in advance. I'll schedule the night shift for myself."

When I got back to the shop, it was already past three o'clock.

A half-finished data sheet lay spread out on the long table. Dania was asleep on it, breathing evenly, a pen still clutched in her hand. Zhou Yu took off his coat and draped it over her back. Just as he straightened up, his sleeve tightened.

She grabbed his sleeve, but didn't wake up, and mumbled a call.

"Xiao Yu."

"Mmm," he replied, "Go to sleep."

He sat there for half the night, his sleeves tied to the table. Chisaki's room upstairs still had its light on, and a recording played over and over again, just those eleven seconds. His other hand was free, so he rewrote the crumpled data sheet line by line. After finishing, he glanced at it and thought, "This overtime was worth it."

The canvas bag lay at my feet, its opening slightly ajar, revealing a glimmer of light.

The memory stone, which had been stuck at 2% for many days, jumped to 5% that night. A line of small characters appeared on the stone's surface. "New entry," just two words.

Gravitational.