Shin Ji-eun had always been aware of the mystery surrounding her father. Her mother never spoke of him, and she had never felt compelled to ask. However, when the Korean National Agency for Intelligence and Counterintelligence (KNAIC) recruited her for a mission, everything changed.

The agency informed her that a madman was on the loose, planning to release an airborne virus that would wipe out a significant portion of the world's population. They also revealed that her father, who she had never met, had once been the leader of the organization until the madman killed him during an undercover mission. Despite her shock, Ji-eun accepted the mission, determined to learn more about her father and find out who killed him.

However, as she delved deeper into the investigation, Ji-eun realized that nothing was as it seemed. After hacking into the agency's database, she discovered that her father was not only alive, but he was the madman who was threatening the world. The revelation left her feeling betrayed and conflicted, but she remained determined to complete her mission and capture her own father to stop his deadly plan.

As the mission progressed, Ji-eun came to question everything she thought she knew. She realized that the truth was even more dangerous than the virus, and the stakes were higher than she had ever imagined. In the end, the mission proved to be critical in more ways than one, and it forever changed Ji-eun's perspective on the world.