Episode 4 of Citadel Season 2 begins with Nadia bleeding on the floor, part of a cunning plan to lure the agents away from her so she can make her escape while Hutch secures the information they need. Unfortunately for Hutch, he forgets the password, leading him to break down the door to the server room. Using the fingerprint of another target they were tailing, he downloads Edison's information. Just as Bantam and Cash arrive, he manages to outsmart them by trapping them inside one of the movable walls. With the information in hand, he joins forces with Frank, and they all escape in a car waiting outside, along with Nadia and Celine. Cash gives chase but is shot in the leg by Hutch, forcing Bantam to turn back.
When they are forced to turn back after an accident blocks the road ahead, Bantam has a clear shot at them, but he hesitates after seeing Frank. It turns out that he, too, was among the marked, and Frank has pictures of him and a prostitute going at it in a hotel. He is married, and this revelation complicates his situation further. Meanwhile, we learn that Edison's real name is Yoo Ha-joon. Nadia knows him as one of the wealthiest men in Korea, a former hacker who went private.
Nadia assumes their next destination is Seoul, but Frank informs them that they will be attending the Greenpeace Annual Gala in Windsor in two days. Ha-joon and his wife are huge contributors and will be hosting the event.
While Orlick and Mason wait for Nadia and the others at the rendezvous point, they confront each other about Mason's betrayal of the Citadel and Orlick's role in killing his father. Orlick explains that they were tracking a terror cell but were betrayed and given the wrong coordinates, resulting in the death of 342 U.N. workers. Mason responds that the agency was keeping his wife from him, so he had to give Dahlia what she wanted, not knowing that she would kill all the Citadel agents. He thinks he and Orlick are the same, but Orlick reminds him that he made a mistake trying to help others, while Mason got thousands of innocent people killed to feed his vengeance. This fundamental difference separates them.
Regardless of their differences, they need to stop Braga, so they must work together. Orlick tells Mason that he doesn't have to worry about being killed behind his back because if he decides to do so, he will do it openly.
In France, Braga educates his son in the art of chess, emphasizing the paramount importance of protecting the King. Meanwhile, in England, Frank reveals Edison's true identity to Aparna. Within the confines of their inner circle, Orlick briefes the team on the plan to kidnap Ha-joon before Braga secures the information. He's aware that Braga will soon acquire the knowledge and pay a hefty sum for it. Hutch and Celine are tasked with neutralizing the target, while Mason and Nadia are to extract him and meet with Orlick and Frank for transportation. As anticipated, Braga receives the intel on Ha-joon and decides to attend the Gala.
At the same time, Mason and Nadia prepare to attend the same party as a married couple, while Celine and Hutch attend as waiters. Celine feels a sense of guilt because she and Hutch are concealing something from the team about Ha-joon. She desires them to come clean, but Hutch believes it's too risky for Celine's life to take that chance. Mason and Nadia manage to sneak into the party. When someone almost captures their picture, Mason pulls her in for a kiss to obscure their faces. While they spy on Ha-joon, they discuss their past relationship with Mason, claiming that he still harbors feelings for her. Meanwhile, Frank and Orlick enter through the staff gate, posing as caterers.
At the Gala, Mason and Nadia continue reminiscing without realizing that someone is silently observing and eavesdropping on their conversation. Meanwhile, Celine and Hutch advance the plan by offering drugged champagne to Ha-joon's wife while Braga calls him away. In a shocking twist, it's revealed that Edison is actually Ha-joon's wife - a secret that Celine and Hutch had been keeping from everyone. While Nadia and Mason go after Ha-joon, Aparna ambushes Celine and Hutch in the washroom when they try to kidnap the wife. She manages to gain the upper hand in the fight, secures the wife, and texts Braga.
Meanwhile, Orlick is aware that Frank is feeding information to Braga's team, so he offers him a higher pay to spy back for them. Braga kills Ha-joon, and when Nadia and Mason go after him, Mason betrays Nadia once again. He tasers her and takes Braga. He lies to Orlick that he has Ha-joon while he secures Braga and drives off with Dahlia.
