"Chief of Staff" season 2 is about an assemblyman who was recently elected named assemblyman Jang Tae Joon (played by Lee Jung Jae) and his struggle to survive in the political world. "Chief of Staff" also features Shin Min Ah (playing Kang Sun Young), Lee Elijah (playing Yoon Hye Won), Kim Dong Jun (playing Han Do Kyung), and Kim Kap Soo (playing Song Hee Seop).
1. From the chief of staff to assemblyman
Lee Jung Jae said that his character is trying hard to hide his true motives. As an assemblyman, he will now turn into an ambitious man. His title and goals will change at the same time. He cannot do things on his own while he is Kim Kap Soo's chief of staff. He needs to influence other people just to accomplish his goals. He turned Kim Kap Soo into a minister of justice and ignored the fact that a worker died at a cement factory which is managed by CEO Lee Chang Jin (playing Yoo Sung Joo), who was the reason for Lee Jung Jae's funding. He did these things for the sake of his nomination. Lee Jung Jae initiated an argument between Kim Hong Fa (playing Jo Kap Young) and Kim Ik Tae (playing Lee Sang Kook), in order for Shin Min Ah's bill to pass. His position as an assemblyman gives him the ability to do the things he wants for his own.
2. From cooperation to distrust
The good relationships full of support and trust from the first season will change into distrust and disapproval in season 2. Shin Min Ah and Kim Dong started not to trust Lee Jung Jae when he was nominated as the new assemblyman. Shin Min Ah saw how hard he worked just to be at the position but seeing him bowing while being insulted by Kim Kap Soo at Lee Sung Min's (Jung Jin Young's) funeral, confused her. Kim Dong Jun used to respect and trust Lee Jung Jae but he got angry with him when he neglected the deaths of workers and the merchants who are struggling at the Seobuk Market. Shin Min Ah and her new secretary Kim Dong Jun's relationship with Lee Jung Jae will turn into misunderstanding and mistrust in season 2. Lee Elijah, Lee Jung Jae's new chief of staff, will be involved with the two.
3. New faces
New characters will appear and their actions are unpredictable. Jung Man Sik who plays Prosecutor General Choi Kyung Chul of the Supreme Prosecutors' Office will threaten Kim Kap Soo and Lee Jung Jae. The drama director said that Choi Kyung Chul will use his logic on politics. Park Hyo Joo (playing the chief of staff Lee Ji Eun) will start to cooperate with Shin Min Ah and make her think that Lee Jung Jae is a bad person. A new man named Jo Bok Rae (playing the chief of staff Yang Jong Yeol), will appear in Lee Jung Jae's office. He will do anything just to achieve his goal. Will he help or threaten Jang Tae Joon?
