She wasn't a professional singer.
But she had inherited her mother's strong voice.
And on evenings when she missed home, she'd sing quietly while washing dishes or walking back from university.
She never imagined the song would someday save a life.
The emergency happened on November seventeenth.
It was a cold Friday evening.
Nia had spent the afternoon at a university language lab, helping a visiting professor prepare transcripts for a seminar on bilingual communication.
By the time she left, darkness had settled over Seoul.
The sidewalks were crowded with office workers, students, and families hurrying home beneath the city lights.
Nia stopped at a convenience store, purchased a small sandwich and a bottle of water, then entered the subway station.
She was tired.
Her backpack was heavy.
And she wanted nothing more than to return to her apartment and call her mother.
The station was unusually crowded.
An announcement explained that service delays were affecting part of the line.
Passengers gathered near the platform doors, checking their phones and speaking impatiently.
Nia stood beside a tiled column and opened a message from Malik.
He'd sent her a short video of himself attempting to cook dinner.
The kitchen was a disaster.
Nia laughed.
Then typed a response telling him never to attempt that particular recipe again.
A little girl standing several feet away looked toward her.
She was eight or nine, with dark hair tied in two neat braids, a pale pink winter coat, and a small backpack decorated with embroidered stars.
The child was holding the hand of an older woman.
She appeared frightened by the crowd.
Nia smiled reassuringly.
The little girl looked away.
Then the lights flickered.
Once.
Twice.
A sharp mechanical sound echoed from somewhere beyond the platform.
The overhead lights dimmed.
And moments later, the station filled with the smell of electrical smoke.
The first seconds were confusing.
Some passengers thought the smell came from a train arriving underground.
Others began moving toward the stairs.
Then an announcement instructed people to remain calm and follow station staff directions.
The lights flickered again.
Someone screamed.
The crowd shifted.
A man dropped his shopping bag.
And suddenly the platform became a mass of frightened people trying to understand what was happening.
Nia moved toward the wall, giving others room to pass.
She heard the little girl crying.
Then she saw something that made her stomach tighten.
The older woman who had been holding the child's hand was several yards away, separated by the movement of the crowd.