Episode 21
Da-dong's parents are missing, now even Arthur's father disappears for no reason. Everyone prepares for a battle of life and death.
More from Season 1 - KO One
Episode 1
Episode 01
The class "KO One" takes students with all kinds of issues. This semester, a transfer student tries to vie for the "boss" position with Da-dong.
Episode 2
Episode 02
The sound of Ding Xiao-yu playing the piano dissolves the tension. Da-dong lends out a helping hand when Arthur's father is in danger.
Episode 3
Episode 03
On the way back from visiting her brother's tomb, Tian Xin is kidnapped and forced to resign her teaching job. Da-dong's buddy returns to the country.
Episode 4
Episode 04
Jin Bao-san witnesses a side of Lei Ke-si that is unknown to others, but Da-dong calls on his classmates to take side jobs to help pay Ke-si's debt.
Episode 5
Episode 05
Lei Ke-si goes out of his way to please all the teachers and classmates while framing Arthur, making it difficult for the latter to reveal the truth.
Episode 6
Episode 06
An unexpected visitor turns up at Da-dong's house. Dean Jia Yong and Lei Ke-si both want to turn An-qi into their pawn.
