The Doctor [D-37 / Pediatric Neurosurgery Clinic]

Professor Kim Dohyun had treated Hajun since birth.

He had been the one to explain the first MRI.

He had also been the one to say Hajun might not live past five.

Taekyung placed a thick binder in front of him.

Dohyun turned the first page.

Then the second.

His expression hardened.

(Dohyun) : “What is this?”

(Taekyung) : “Data from accelerated neural organoids.”

(Dohyun) : “I can see that.”

Dohyun closed the binder.

(Dohyun) : “I’m asking why you brought it to me.”

Taekyung answered.

(Taekyung) : “I want to transplant it into Hajun.”

Dohyun said nothing for a long time.

Then he pushed the binder back.

(Dohyun) : “No.”

(Taekyung) : “You haven’t even reviewed all the data.”

(Dohyun) : “I don’t need to.”

(Taekyung) : “Long-term survival was confirmed in animals. Vascular integration too. Bidirectional signaling—”

(Dohyun) : “Professor Taekyung.”

Dohyun’s voice lowered.

(Dohyun) : “This is not treatment. It is an experiment.”

Taekyung nodded.

(Taekyung) : “I know.”

Dohyun’s expression tightened further.

(Dohyun) : “And you still want to do it to your son?”

(Taekyung) : “Yes.”

(Dohyun) : “Isn’t this exactly the kind of thing you spent your entire career condemning?”

Taekyung could not answer immediately.

Dohyun opened the binder again.

(Dohyun) : “You don’t know what will happen in a human brain. The seizures could get worse. The tissue could grow abnormally. You don’t know what it could do to personality or function.”

(Taekyung) : “I know.”

(Dohyun) : “What’s the success rate?”

Silence.

(Dohyun) : “You can’t calculate it, can you?”

(Taekyung) : “No.”

(Dohyun) : “Then the answer is no.”

Taekyung gathered the binder.

At the door, Dohyun spoke again.

(Dohyun) : “Hajun is my patient too.”

Taekyung turned.

(Dohyun) : “That’s exactly why I can’t do it.”

[D-22 / Hospital Room]

Hajun deteriorated quickly.

Short seizures came several times a day.

He ate less.

A child who had once walked on his own now needed someone to hold his hand again.

One day, Hajun stared at a picture of a yellow bus and could not speak for a long time.

Jian waited.

(Jian) : “Hajun, what color is this?”

Hajun’s lips moved.

No word came out.

Jian kept smiling.

(Jian) : “It’s okay. Take your time.”

Taekyung stepped out into the corridor.

At the far end, he ran into Dohyun.

Dohyun spoke first.

(Dohyun) : “Do you have more data?”

Taekyung looked at him.

(Dohyun) : “Anything since the last time.”

Without a word, Taekyung handed him a USB drive.

[Dawn / Doctors’ Office]

Dohyun reviewed the data alone.

Developmental acceleration.

Vascularization.

Long-term survival.

Integration in animals.

Seizure risk assessment.

He went over the same files again and again.

The next morning,

he opened Hajun’s MRI.

The normal brain tissue that remained.

The areas of declining function spreading wider.

Modern medicine was running out of things it could offer him.

[D-12 / Hospital Rooftop]

Dohyun said,

(Dohyun) : “There’s no guarantee surgery will save him.”

(Taekyung) : “I know.”

(Dohyun) : “He could die during surgery.”

(Taekyung) : “I know.”

(Dohyun) : “Even if he survives, something could happen that neither of us predicted.”

(Taekyung) : “I know.”

Dohyun sighed.

(Dohyun) : “Is that all you can say?”

Taekyung was silent for a moment.

(Taekyung) : “What happens if we don’t do it?”

This time, Dohyun had no answer.

They both knew.

Dohyun looked beyond the railing.

(Dohyun) : “We can’t do this officially.”

Taekyung’s eyes moved.

(Dohyun) : “And I don’t believe this choice is right.”

Taekyung said nothing.

Dohyun turned toward him.

(Dohyun) : “But I also can’t say waiting for Hajun to die is better.”

After a long silence,

Dohyun said,

(Dohyun) : “Bring me the surgical plan.”

From that day on, they were no longer just a doctor and a parent.

They were accomplices carrying the same secret.