Yoon Hyein is leaning towards Lee Jungwoo, whether or not he believes it. She constantly drops him hints on Athena’s plans, but he can’t help but think of her as a traitor whom he once loved.

Just as Yoon Hyein is about to go help Lee Jungwoo, she’s caught and brought to NTS as a member of Athena under arrest.

Furious, Lee Jungwoo almost immediately storms into her interrogation room. How? Why? She remains silent. His temper is so uncontrollable that he can’t even see that for once, she is full of regret. Remorse. She has a conscience and she isn’t the same as before. If only he could see the water in her eyes.

After the interrogation is over, Yoon Hyein requests to speak with Lee Jungwoo. She tells him sorry. She tells him that she always used to have nightmares, but after meeting him, they stopped coming. Now it’s his turn to give her the cold shoulder. Lee Jungwoo, still bitter, tells her that it must be his turn to have the nightmares now. :'( Yoon Hyein is transferred somewhere else, and Lee Jungwoo goes drinking with the director. The director, aware of Yoon Hyein’s true colors, tells Lee Jungwoo that he has done something that he (himself) wouldn’t be able to do. He became a part of someone’s life and changed it for the better. Lee Jungwoo starts to realize that he was wrong.

Son Hyuk, still treating Yoon Hyein as family/girlfriend, puts bombs in NTS so that they will hand over Yoon Hyein. They hand her over, but he still has the bombs.

Yoon Hyein, who has fully transformed into a different person now, is even willing to sacrifice for the people of NTS, not just Lee Jungwoo. Aware that Son Hyuk can let the bomb go off whenever he wants to, she points  a gun to him. Betrayal. Big time. Son Hyuk is a brother and a father to her, her only family member. She is willing to betray him. Son Hyuk, shocked, tells her to shoot. My heart only beats for you anyways. Yoon Hyein can’t do it, but that doesn’t mean that she won’t betray him in the future. Dun dun dun.

Bonus Yoon Hyein screencaps below. Look at those flips and kicks. It’s like gymnastics and martial arts mixed into one.

Screen caps from episodes 14-16.