Contains spoilers for this episode and earlier episodes.
Han-na secretly delivers evidence of the North-South arrangement to news outlets, but Soo-ho and Gang-mu wait for a report that never appears. Chang-su obtains the material and orders her arrest, forcing her to flee. The Northern leadership has also learned that Soo-ho is cooperating with Gang-mu. Outside, officials prepare explosives around the dormitory and threaten to destroy it if the people inside disrupt their scheme. Soo-ho tries to persuade Chung-ya that she can choose a life beyond the mission, even after she attacks him with a knife. Yeong-ro asks him to survive and see his sister again, while he promises to protect her and her friends.
Searching for the leak, Gang-mu and Soo-ho question Bun-ok and learn that an intercepted message came from the dormitory while Soo-ho was absent. Someone else has been operating there. A radio hidden among the kitchen supplies directs suspicion toward cook Deok-sim, although her condition makes the accusation difficult to assess. Yeong-ro proposes speaking to her father herself before the confrontation becomes an assault. Chang-su comes to meet her at the chapel, where she begs him to save everyone rather than extracting her alone. When he tries to hold her, she pulls away and shields Soo-ho as the armed officers move. The meeting fails to produce a safe departure, and Chang-su is shot as the situation outside breaks into gunfire.