Contains spoilers for this episode and earlier episodes.
The gunshot came from a struggle inside the vehicle, leaving Se-ri alive but in the hands of Jeong-hyeok’s father. Jeong-hyeok does not know this when he clashes with Cheol-gang during a search of his house and is detained. He asks Dan to pass on a warning: if his father hurts Se-ri, he will lose his remaining son. The soldiers spread news of his family connections to secure his release.
Se-ri initially mistakes her captor for Dan’s father and tries to protect Jeong-hyeok by taking responsibility for everything. His mother brings her to a warmer room and treats her gently. When Jeong-hyeok arrives in distress, she ends his uncertainty by bringing Se-ri out. Later, Se-ri plays the melody she heard in Switzerland. He recognises the song he wrote for his brother, and they realise his music had reached her years before.
Cheol-gang’s attempt to expose the family fails when a search finds no trace of Se-ri. Jeong-hyeok arranges an emergency company switch so his own men can guide her through familiar terrain to the border. She shares a farewell with the squad before walking the final stretch with him. He tells her how to reach the South Korean rescue team, then steps across the line for a goodbye kiss as she finally makes her way home.