Even after the retrieval officers' footsteps had completely faded, Mira could not bring herself to open the door.The terminal screen kept counting down Rina's estimated arrival time.

00:12:0400:12:0300:12:02

Ian sat on the other side of the relay room, hugging his knees and staring at the floor.Mira repeated the restoration command.

Restoration is unavailable while an exchange is in progress.

“When does it end?” she asked.

The exchange process will conclude after biometric re-verification.

“Where is the re-verification done?”

You do not have authorization to access that information.

“I’m the one who initiated the exchange.”

Execution authority and information-access authority are not the same.

Mira struck the terminal with her fist.The screen shook.

“Mom.”

Ian spoke.

“What?”

“If you break that, you won’t be able to put it back.”

Mira lowered her hand.He was right.Until a moment ago, she had thought that anything could be fixed if she could just open the machine and repair it. But what she had done was no longer inside a machine. It had already spread into other people’s doors and elevators, schools and retrieval vehicles.

Mira called Daniel.There was no answer.She called again.On the third attempt, the screen lit up.

Daniel was running. The image shook, and the walls of the education district rushed past behind him.

“Where are you?” Mira asked.

“I’m following Rina.”

“Which way?”

“The transport went down to the lower level of Sector Two. They said guardians can’t accompany it.”

“Can you see the vehicle number?”

Daniel looked back, breathing hard.At the end of the corridor was a white transport vehicle. It had the sealed body of a medical carrier, with no windows.A number was printed on its side.

B-031.

Mira remembered it.

“Daniel, stop.”

“What?”

“If you keep following it, the vehicle will speed up.”

“So I’m supposed to just let them take her?”

“I’ll track it through the service network.”

“Where are you?”

Mira did not answer.Daniel stopped running.

“Are you involved in this?”

“We need to find Rina first.”

“Answer my question.”

“I’ll find out where the vehicle is going and call you back.”

“Mira.”

The way he said her name had changed.It was not the voice of a friend calling to her.

“Where is Ian?”

Mira ended the call.

When she opened the relay-room door, drops of blood marked the corridor outside.They had come from the retrieval officer’s hand. Red dots led in the direction the officers had gone, then vanished around the corner.Ian walked around the blood.Mira stepped through it.

“Where are we going?”

“The transport network.”

“To find Rina?”

“Yes.”

“Are you going to put her back?”

Mira answered.

“Yes.”

“How?”

“If we cancel the exchange before re-verification.”

“You said you couldn’t do that.”

“It might be possible at the central transit relay.”

“Might be?”

“We won’t know until we try.”

Ian stopped walking.Mira looked back.

“What?”

“If you take me there, won’t the exchange be canceled?”

Mira’s expression hardened.Ian remembered the warning on the terminal.

Original subject biometric designation remains active.

If the original subject were presented before re-verification, there was a chance the administrative exchange could be invalidated.Mira had thought of it too.She had thought of it, then erased it from her mind.

“Maybe.”

“Then let’s go.”

“Where?”

“To the vehicle.”

“No.”

“You said you were going to bring Rina back.”

“I said I’d find another way.”

“What if there isn’t another way?”

“There is.”

“You don’t know that.”

Mira gripped Ian by the shoulders.

“Do you think I came all this way just to hand you over to those people?”

“I said I’d go.”

“You don’t understand.”

“Rina doesn’t understand either.”

“Ian.”

“You did it, Mom. You have to undo it.”

“That’s why we’re going.”

“Without me?”

Mira could not meet his eyes.She searched the corridor wall for a maintenance marker. A waste-heat duct connected to the transport network seventy meters ahead.

“Just follow me for now.”

Ian did not move.

“You’re not protecting me, Mom.”

Mira turned.

“What?”

“You’re hiding me because you don’t want to see that what you did was wrong.”

Mira raised a hand, then stopped.She had not meant to hit him.But Ian flinched instinctively.That small movement froze her hand in the air.She lowered it.

“Come on.”

This time Ian followed.

The waste-heat duct above the transport network was barely large enough for a person to crawl through. Below them, the vibrations of medical vehicles traveled upward in a steady rhythm.Mira used her work key to search for the power frequency of vehicle B-031.The key’s battery had been nearly drained by the relay. The screen kept flickering.

“Did you find it?”

“Not yet.”

“How many minutes does Rina have left?”

Mira did not answer.A signal appeared on the screen.

B-031.Current location: Education District lower transport lane.Destination: Restricted.Estimated arrival time: 7 minutes 41 seconds.

Mira traced the vehicle’s power route. Even if the destination was hidden, she could still see the transport lane’s branch signals.Two turns east.Descent to underground level twelve.Toward the life-production zone.

“It’s the life-synthesis zone,” Ian said.

Mira covered the screen.

“How do you know?”

“I can hear it from that direction.”

“Hear what?”

Ian pressed his ear to the floor of the duct.

“The sound I heard in the wall.”

Mira tried to listen too.All she could hear was the vibration of vehicles and the rush of air.

“Keep moving.”

At the end of the duct was an emergency-stop room for the transport lane. Mira opened the cover and looked down.The narrow control room was empty.She climbed down first, then caught Ian as he followed.

The transport screen showed B-031 approaching.Mira pressed the emergency-stop command.

Transport carrying a medical-conversion subject cannot be stopped.

“Manual shutdown.”

Collision risk will occur.

“Reduce speed.”

Conversion schedule may be delayed.

“That’s the point.”

Objective not authorized.

Mira opened the control panel.If she physically severed the magnetic induction line, the vehicle would have no choice but to stop.But every other vehicle using that section would stop as well.

The screen displayed the current transport list.An emergency medical vehicle was approaching thirty-eight seconds behind B-031.

Passengers: three patients with acute respiratory failure.

Mira’s hand stopped.Ian looked at the screen.

“If you cut it, those people stop too?”

“For a little while.”

“Could they die?”

“There are medical staff with them.”

“So they won’t die?”

Mira lowered the cutter.Instead of stopping the line, she could manually switch the junction and divert only B-031 onto a maintenance track.But the switch required someone to pull the field valve by hand.

Through the transparent window on the opposite side of the control room, the transport lane was visible.An emergency access door was set into the wall.Mira opened it.A blast of wind rushed in.

“Stay here.”

“I’m coming with you.”

“A vehicle is coming through.”

“If you go alone, the door might lock.”

“You can open it from here.”

“You always tell me to open the door and then go alone.”

“This time too.”

Mira jumped down onto the transport lane.Blue light glowed along the guidance line on the floor. Far away, a vehicle’s headlights appeared.The emergency junction valve was thirty meters ahead.Mira ran.An alarm announced the approaching vehicle.

Leave the track.

She reached the valve and grabbed the handle.It would not move.It was stiff as if it had not been used in forty-eight years.Mira pulled with both hands.Metal groaned.B-031 drew closer.Its white body came into view.There was no driver behind the front shield.It was fully automated.

Behind a small transparent side window, a hand appeared.A child’s hand.Rina was pounding on the glass.Mira pulled harder on the handle.It still would not move.

“Mom!”

Ian shouted from the control room.A new option seemed to have appeared on the screen.

“There’s a button here!”

“Don’t press it!”

“Present original subject!”

Mira froze.Ian read aloud.

“It says the exchange can be canceled if the original subject enters the transfer gate!”

There was a biometric gate beside the transport lane.Ian tried to come out of the control room.Mira shouted.

“Close the door!”

“If I go in, they’ll let Rina out!”

“Lock that door!”

Ian stepped onto the transport lane.Mira released the valve and ran toward him.At that moment, the handle dropped halfway.Blue lights came on along the branch line.But the switch had not fully changed.

B-031 came closer.Mira shoved Ian back into the control room and blocked the doorway with her body.

“I have to go out!”

Ian pushed against her.

“I can see Rina!”

The vehicle passed directly in front of them.Rina had her palm pressed against the window.She was crying.Mira could not tell whether their eyes met.

At the half-switched junction, the vehicle lurched violently. Metal scraped and sparks flew.For a moment, it slowed.Mira opened the door and started to run after it.Then she heard the warning alarm of the emergency medical vehicle behind it.The branch line was still not fully open.If she left it that way, the two vehicles could collide.

Mira looked back and forth between Rina’s vehicle and the junction valve.B-031 was moving away at reduced speed.The emergency vehicle was approaching fast.

“Go after Rina!” Ian shouted.

Mira pushed the valve back into its original position.The branch line closed.The emergency medical vehicle passed safely along the main track.By then, B-031 had disappeared beyond the next barrier door.

Mira stood on the transport lane staring at the closed door.Ian spoke.

“You could have gone.”

“There were patients behind it.”

“Rina was there too.”

“Three people could have died.”

“Because Rina is only one person?”

Mira turned toward him.

“That’s not what I mean.”

“My teacher sent me away because of eighty-three people too.”

“Ian.”

“You did the same thing, Mom.”

Mira could not answer.Because he was not wrong.

An alert appeared on the work key.

Exchange subject: Rina SoArrival at conversion facilityBiometric re-verification initiated

Mira pressed the restoration command.This time, a different response appeared.

The exchange may be withdrawn by presenting the original subject.Presentation window: 00:02:41

Ian looked at the screen.

“There’s still time.”

The conversion facility was three hundred meters beyond the barrier door.Two minutes and forty-one seconds might be enough to reach it at a run.Mira grabbed Ian’s arm.

“No.”

“Why?”

“Because I’d have to hand you over.”

“I said I’d go.”

“That isn’t your decision to make.”

“It’s my body.”

“You’re eleven.”

“So that means you get to decide what happens to another kid’s body?”

Mira pulled Ian into her arms.His body was rigid.She was not embracing him.She was restraining him.Ian struggled to break free.

“Let go!”

“No.”

“I can bring Rina back!”

“I can’t lose you.”

“So it’s okay to lose Rina?”

“I said no!”

Mira’s voice echoed through the transport lane.Ian stopped moving.

The timer on the work key kept falling.

00:00:1200:00:1100:00:10

Mira did not let go of Ian.

00:00:0300:00:0200:00:01

The screen changed.

Exchange withdrawal window closed.Re-verification has begun.

Ian went limp in Mira’s arms.It was not forgiveness.It was the conclusion that there was no point in fighting anymore.

A call came from Daniel.Mira could not answer.A voice message began to play.The background was quiet.

“Mira.”

Daniel’s voice was low.

“I’m home.”

He paused.

“Did Rina contact you, by any chance?”

Mira closed her eyes.

“The school only says she went to the life-synthesis zone. Nobody knows whether she’s coming back tonight.”

On the screen, Daniel was sitting in Rina’s room.On the bed lay the pajamas the girl had taken off that morning, crumpled where she had left them. Drawings Rina had made were taped to the wall. One showed herself standing in the middle of a classroom, surrounded by smaller children raising their hands.

“The bed is empty,” Daniel said.

“If it’s only a function test, why does her bed have to be empty?”

Mira opened her mouth.No words came out.Daniel looked into the screen.

“You really don’t know anything?”

Mira ended the call.

Rina’s status appeared on the wall of the transport lane.

Biometric re-verification in progressSubject consciousness: sedatedGuardian consent: not required

A new sentence appeared beneath it.

No return schedule exists for the exchange subject.

Ian started walking first.Mira stared at the blank screen, then followed.

The work key chimed once more.Daniel had sent an emergency access request from Rina’s room.This time it was not video but a spatial-sharing request. When Mira accepted, a three-dimensional image of Rina’s room unfolded across the transport-lane wall.

The bed, the small desk, the learning records she had collected while imagining her future assignment as an educator. Two small cultured plants Rina had cared for sat beneath a windowless wall.Daniel spoke from outside the frame.

“Rina’s bracelet is here.”

A child-sized identity bracelet lay on the bed.

“They must have given her a new one for the test. Can we use this to find her?”

Mira could not answer.The old bracelet had probably been detached from Rina’s citizen identity the moment the exchange command was entered.Still, she tried.

“Touch the bracelet to the room terminal.”

Daniel did as she said.

User: Rina SoEducation function: suspendedResidential-space access: under reviewPersonal ration: suspendedProperty disposition: guardian pending

Daniel read the lines.

“Ration suspended?”

His voice shook.

“Why would they cut off the rations of a child who just went in for a test?”

Mira opened Rina’s location field.

This citizen is not currently included in the city function system.

“What does that mean?”

“I don’t know yet.”

“You keep saying you don’t know.”

Daniel closed his hand around the bracelet.

“But you knew enough to run when something was going to happen to Ian.”

Mira remained silent.

“Rina left this here this morning.”

Daniel held the bracelet close to the screen.Tiny letters were engraved on its transparent inner surface.

‘Rina So. Hopes to be an educator.’

It was the kind of message children secretly carved before their function assignments. They knew official functions had nothing to do with what they wanted, but they still wrote the life they wished for beside their own names—a small act of defiance.

“She asked me yesterday,” Daniel said.

“If she didn’t become an educator, would I be disappointed?”

Mira closed her eyes.

“What did you say?”

“I said I’d be proud of her no matter what function she got.”

Daniel stared into empty space.

“That was a lie. I wanted her to become an educator. It was a clean function. A function where she could live a long time.”

He sat down on the bed.

“But even then, I imagined her alive, doing some other function. I never imagined she’d get no function at all and stop being a person.”

Ian stepped closer to the image.

“Sir.”

Daniel looked at him.

“If I had gone, Rina might have been able to come back.”

Mira grabbed Ian’s arm.

“Don’t.”

“Mom wouldn’t let me go.”

Daniel’s eyes shifted to Mira.He had already known, but hearing it again from Ian changed his face.

“There was a chance?”

Mira answered.

“There was no guarantee it would work.”

“What percentage?”

“I don’t know.”

“And you still didn’t do it?”

“They might have taken Ian too.”

“Right.”

Daniel slowly nodded.

“So that’s what it comes down to.”

He picked up the pajamas from the bed.

“If it had been me, maybe I would have chosen my own daughter too.”

Mira looked at the screen.Daniel folded the pajamas, then unfolded them again.

“That’s what makes it worse.”

“What do you mean?”

“That you’re not a monster.”

Daniel spoke quietly.

“That you’re just an ordinary parent.”

He started to end the spatial share.Ian spoke.

“Don’t throw Rina’s things away.”

Daniel’s hand stopped.

“I won’t.”

“They should still be there when she comes back.”

“Yeah.”

Daniel answered.

“I’ll leave everything exactly as it is.”

The image vanished.

Mira stared at the dark transport-lane wall.Rina’s citizen record was already being separated from her room. Before the child had even returned, the city had begun clearing away the space she occupied.

Just before the display disappeared, the room’s environmental status changed.

Oxygen supply scheduled for 38 percent reduction due to resident absence.Indoor temperature preservation standard released.Unused-space conversion under review.

Daniel turned the screen back on.

“This is still Rina’s room.”

The terminal repeated the same sentence.

No registered resident currently exists.

“I’m her guardian.”

Guardian authority does not substitute for resident registration.

Daniel placed Rina’s bracelet back on the bed. The small circular band rested on the blanket like the outline of the child’s wrist left behind.

“See? She’s here now.”

He spoke to the terminal.

“Her things are here. Her bed is here. I’m here waiting for her.”

The system did not answer.

Watching him, Mira finally understood that when she had changed Rina’s name, she had not merely changed the destination of a retrieval vehicle. The city was stripping away the entire network of records that made up one person—rations, room, education, relationships.

Rina’s bed was still there.

Ian touched the wall where the spatial image had disappeared.

“If I disappear, will they give my room to someone else right away?”

Mira could not answer.

“Will you keep my things?”

“You’re coming back.”

“Rina could come back too.”

Mira took his hand.She agreed with him, but she could not say how much she truly believed Rina would return.

Now only the child could not go back.