Through the Looking Glass CEO

Because she looks exactly like the female CEO who just died unexpectedly. In order to stabilize the stock price, the board of directors secretly found her and asked her to pretend to be the CEO for three months. On the surface, the heroine is a "puppet", but in fact, she uses this identity to find out the truth about the death of the female CEO step by step, and turns against customers in the business war to become the real person in power.