Plot: The school's security guard dies, leaving Hae Seong a notebook belonging to his missing father. The revelation is shocking, and he storms the NIS for answers
Cast
Seo Kang-joonJeong Hae-sungSeo Kang-joon was 31 in Undercover High School - Season 1 - Hye Seong's Father's Notebook (Episode 6).
Birthday: Tue, Oct 12 1993
Jin Ki-jooOh Su-ahJin Ki-joo was 36 in Undercover High School - Season 1 - Hye Seong's Father's Notebook (Episode 6).
Birthday: Thu, Jan 26 1989
Kim Shin-rockSeo Myung-juKim Shin-rock was 43 in Undercover High School - Season 1 - Hye Seong's Father's Notebook (Episode 6).
Birthday: Tue, Mar 24 1981
Kim Min-juLee Ye-naKim Min-ju was 24 in Undercover High School - Season 1 - Hye Seong's Father's Notebook (Episode 6).
Birthday: Mon, Feb 05 2001
Yoon Ga-iPark Mi-jungYoon Ga-i was 24 in Undercover High School - Season 1 - Hye Seong's Father's Notebook (Episode 6).
Birthday: Sat, Sep 16 2000
Kim Young-ahIm Chung-haKim Young-ah was 49 in Undercover High School - Season 1 - Hye Seong's Father's Notebook (Episode 6).
Birthday: Mon, May 12 1975
Lee Hyeon-soHan Seung-jaeLee Hyeon-so was 26 in Undercover High School - Season 1 - Hye Seong's Father's Notebook (Episode 6).
Birthday: Mon, Mar 08 1999
Kim Seung BeomKim Ho Jin [Informant]Kim Seung Beom was 23 in Undercover High School - Season 1 - Hye Seong's Father's Notebook (Episode 6).
Birthday: Mon, Jan 21 2002