Dokgo Rewind (2018)

"Dokgo Rewind" is based on webtoon of the same name, and it is prequel to the webtoon "Dokgo". The story begins one year before "Dokgo" (before Kang Hyuk seeks revenge for his twin brother). Kang Hyuk and his mischievous friends meet Kim Gyu Soon and decide to help him protect his sister. Things escalate and Kang Hyuk and his friends end up fighting against high school delinquent gangs.