Follows Rim Chul Ryung heading back to South Korea in pursuit of a brutal and secret criminal organization. He teams up again with Kang Jin Tae, who volunteers to work with the North Korean in order to get back on the investigation team after a mistake landed him in the cyber crime department.

Do Min-Ik works as a director of the mobile media 1 team at T&T. He is smart and excellent at his job. His secretary is Jung Gal-Hee. Do Min-Ik often does childish things like calling Jung Gal-Hee continually. Jung Gal-Hee carries out Do Min-Ik's orders without complaints. She looks soft, but she hides her tough side.

Inevitably, everybody gets hurt at some point in their lives. There are different remedies for different types of wounds, and as time elapses, these remedies start to become less effective. This is a story about a man who created a shield for his broken heart. Since the day his heart broke, he has been living inside a shell. One day, he encounters a being unlike any other, and by interacting with her, he slowly learns how to break out of his shell.