Plot: Baek Chan-Mi (Choi Gang-Hee) was a legendary black agent for the NIS, but, due to her excessive work, her subordinate died and she missed catching her intended target. Baek Chan-Mi was punished for that botched case and she now works in a cyber security team for the NIS. Baek Chan-Mi is then selected to go undercover on a case involving intellectual property theft at Korea's largest company.