In episode 1 series 'Kill It', Jang Ki Yong (Jang Ki Yong) from an early age had to undergo harsh training to become a cold-blooded assassin. Father Pavel taught him the principles of survival, but he was also the one who turned Soo Hyun into a sadistic killer.
Soo Hyun was the target that Pavel had to eliminate, but he took care of him and raised him. With Soo Hyun, Father Pavel became a family, a really important person in his life. He replaced Soo Hyun with the task of eliminating the target, but Alzhermer's disease was increasingly ingrained in him, causing Pavel to fail and be arrested. Although he appeared in time but still could not save him, this made Soo Hyun extremely hurt. After the assassination, Soo Hyun was constantly chased by the enemy. As soon as Pavel's father died, the image of Soo Hyun's previous family photoshoot was also gradually added. He also quickly returned to work and anonymously as a veterinarian.
Do Hyun Jin (Nana) is assigned to investigate the murder on the mountain with the expectation of breaking this serious case. Hyun Jin showed the ability to think very well and sharp when guessing almost the details of Soo Hyun's murder process. However, things continue to go into a dead end because of the very random appearance of a new suspect who is supposed to be the culprit. The case was suddenly closed with countless suspicious points that Hyun Jin could only quietly investigate himself. She herself knew that the suspect was not the culprit, but accepting him was the way the real assassin would show up.
The fact that Hyun Jin insisted on pursuing this case because the method of elimination was similar to killing her boyfriend many years ago. The obsessive past makes Hyun Jin always try to find the killer and the only witness in the murder. It is not too difficult to understand when the wound has turned her into a cold form like today.
Because Hyun Jin and Kim Soo Hyun had the first unhappy meeting, they were enough to leave an impression on each other. At first it was accidental but the next time it might be destined to be arranged, two strangers suddenly intersected at unexpected events. The thing that Hyun Jin was completely unexpected about was that she had become the target Soo Hyun was watching.