<Korean TV Series NOW> ”Undercover High School” EP5, Seo Kang Joon struggles among those who are pursuing his identity = Viewership rating 7.2%, Synopsis and spoilers

*This article contains spoilers. In EP5 of the MBC TV series "Undercover High School" (viewership rating: 7.2%), Hye-sung (Seo Kang-Joon) reveals her true identity.
The story depicts his struggle among those who are chasing him. Hee-sung succeeds in being in the top 10 in the school, which is one of the conditions to become a student council officer. Furthermore, he tries to win the right to be selected as an officer so that he will not lose to others.
Although he showed slight affection for YENA (Kim Min Ju), who had a limited interest in him, the atmosphere quickly cooled, but he was still selected as a student council officer in the finals.
Meanwhile, Hye-sung went to the student council room in the middle of the night to look at the wall clock and said, "I'm glad to meet you.
Then he receives a mysterious letter with the message, "I'm sorry." Then he receives a call from Mr. Kim (Koo Min-hyuk), a security guard who claims to know his true identity, asking him to meet him on the school rooftop.
Then the clock struck midnight, and shortly afterwards, Mr. Kim was found dead, clutching Hye-sung's father Jaehyun's diary in his hand, leaving Hye-sung confused.