Set in Shanghai in 1948. A traitor tells information about a high-level CCP undercover and Nationalist secret service tries to find him out.

Lin Xi who's known as the "witch" in the translation industry reunites with ex-boyfriend Xia Yicheng. Eight years ago, she broke up with him for the sake of fulfilling her mother's wish for her to become a professional interpreter for the United Nations. Eight years later, Lin Xi has become the youngest chief interpreter at Huasheng while her ex Xiao Yicheng has become the chief technology officer of a communications company, which also makes him her potential client. In order to land a contract with Xiao Yicheng, Lin Xi has no choice but to keep dealing with him. She helps his company go public and even though it seems that Xiao Yicheng is out to get revenge on Lin Xi, he actually doesn't have the heart to be mean to her. Work rekindles their passionate relationship and Xiao Yicheng gradually comes to understand that reason she broke up with him. Together, they work hard to realize their dream of "speaking for the country".