<Korean TV Series NOW> ”Undercover High School” EP12 (final episode), Seo Kang Joon completes his mission = Viewership rating 5.8%, Synopsis/Spoiler

*This article contains spoilers. In EP12 of the MBCTV series "Undercover High School" (viewership rating: 5.8%), the group completed their mission to retrieve Emperor Gojong's gold.
The story depicts Hye-sung (Seo Kang-Joon), Soo-ah (Jin Ki-Joo) who achieves her dream of becoming a full-time teacher, and Myung-ju (Kim Shin-Rock) who has to atone for her sins.
Hye-sung barely escapes from the overturned car and is saved by Su-a. With a wanted poster issued for the murder of Director Kim (Lee Seo-hwan), Hye-sung is helpless and retreats to the neighborhood where she is.
He called together four teams from the National Intelligence Service in Korea. They had to go and find a USB containing evidence to get rid of Myung-ju, but they ran into the police on the way out.
While the four domestic teams waited in front of the door to buy time, Hye-sung lured the police away while Su-a went to the school to protect the children.
Unable to return home due to being on the wanted list, Hye-sung makes use of Team Leader Kong (Lim Cheol-hyun).
Myung-ju did it. The evidence is in the USB in the house." Team Leader Kong believed Hye-sung's words and took the USB, and Hye-sung immediately went to the police station and committed suicide.
Myung-ju said, "In order to minimize the backlash from the students, we will not abolish the scholarship system or raise tuition fees, let alone cheat on the school report.
However, at this time, Yoo-jung (Park Se-hyun) started asking why Su-a was expelled, and then the other students also rebelled and cornered Myung-ju.
Meanwhile, an arrest warrant was issued for Myung-ju and Jae-moon (Park Jin-woo), and the National Intelligence Service's Domestic Team 4 went to the school to capture them. At that time, a fire alarm went off and a spring came down from the school.
The blast explodes, the school is covered in gasoline, and Myung-ju terrorizes her with a lighter. When Hye-sung arrives at the school, she approaches Myung-ju with a gun, and the two engage in a fierce standoff.
At that moment, YENA (Kim Min Ju), who had returned home, returned and began to try to stop Myung-ju. As the tension intensified, Myung-ju pointed a gun at her own head.
When he pulled the trigger, Sua jumped in and barely managed to save him. That was how the whole situation ended, and Myungju and Jaemun were put on trial. At first, Jaemun said, "I'm the one who killed everything.
However, Hye-sung persuaded her and Myung-ju was given the appropriate punishment of life imprisonment.