Shinbyeong 4 Episode Ends with Promotions, Apologies, and the Season's Most Emotional Farewell Yet

The September 22 episode of Shinbyeong 4: Sabotage (ENA) packed three major emotional beats into one hour: the discharge of Kang Chan-seok and Choi Byeong-nam, a round of long-overdue apologies, and a quietly devastating moment when squad commander Jo Baek-ho finally saw his name on the promotion list.

With just one day left before discharge, Jeon Se-gye (Kim Dong-jun) announced that Kang Chan-seok (Lee Jung-hyun) and Choi Byeong-nam (Kim Hee-su) were almost out. The two had voluntarily delayed their discharge to take part in national defense training, and they were paying for it physically. "Muscle pain in my final days," Kang Chan-seok complained. "I can barely get up," Choi Byeong-nam added. The kind of exhausted, self-inflicted suffering that only makes sense in the military.

Lucky signs and small kindnesses

In the lead-up to their last day, both soldiers started noticing small strokes of luck that felt almost too pointed to be coincidence. A hardtack biscuit split open to reveal two star-shaped candies instead of one. A cigarette appeared beside Choi Byeong-nam just as he thought he'd run out. The vending machine returned change no one expected, so they drank free coffee. It reads as the show doing what it does best: letting small, mundane details carry the weight of something larger.

Mun Bit-na-ri (Kim Yo-han) spent his last hours helping Kang Chan-seok prepare for the college entrance exam. "The commander told me to help you through to the end," Mun Bit-na-ri explained. Kang Chan-seok was visibly moved. "I didn't think anyone would go this far for me." Mun Bit-na-ri had drawn up a full study schedule and tracked down contact information for a tutoring center, and when the other soldiers presented Kang Chan-seok with study materials and exam supplies as a goodbye gift, it was Mun Bit-na-ri who cried on his behalf. Choi Byeong-nam received his own farewell gifts and didn't make it through dry-eyed either.

Later that night, the two were summoned to what they assumed was the commander's office, and walked straight into the ritual discharge prank the Korean military is known for. The show plays it warm rather than hazing-adjacent, which is the right call.

Apologies and a final goodbye

The more affecting scene came when Kang Chan-seok sat down with Jo Baek-ho (Oh Dae-hwan) and admitted he'd spent a long time regretting his past behavior. "No matter how well I do now, it doesn't erase what happened," he said, and the honesty of it landed. Jo Baek-ho responded with genuine warmth, encouraging both men as they prepared to leave. Choi Byeong-nam thanked him simply: "Thanks to you, commander, I'm leaving with good memories."

Before the discharge, Jo Baek-ho quietly stepped aside so Kang Chan-seok could have a private moment with Kim Dong-u (Jang Seong-beom). The apology between them, "I was really sorry to you", and Kim Dong-u's response, that the difficult period had helped him grow, was the episode's most understated and effective exchange. On discharge day itself, Kang Chan-seok broke down crying, apologized to Kim Dong-u one final time, and told him he was leaving with only gratitude. The two rode off in a convertible, Shinbyeong 4's signature discharge send-off, into whatever comes next.

Jo Baek-ho's long-awaited promotion

Amid all of that, the episode saved one more moment for the very end. Jo Baek-ho checked the promotion list and found his name on it. He had been quietly anxious about it for some time, giving nothing away to the soldiers around him. When confirmation finally came, he swallowed his emotion rather than let it show. The squad, for their part, offered him their genuine congratulations on the upcoming promotion to major. Oh Dae-hwan plays the restraint beautifully, a single held breath, a barely-there smile, and it's the kind of performance beat that earns the response it got online. For a character who has spent the season holding everyone else together, seeing him finally exhale felt like the episode's real ending.