She's clever, witty, and very full of herself. Yoo Jeongyeon is the Vice chairperson of Yoo Group, the largest company in South Korea. Myoui Mina has been her secretary for 9 years but suddenly, she decides to resign from her job. Baffled, Jeongyeon decides to dig deeper, trying to find the reason for why she has decided to resign. What exactly is wrong with secretary Myoui ?