This season picks up where Season 2 left off. With the timeline reset and the KO ranking restored, we see the return of some familiar faces from Season 1.Wang Da Dong joins Xiu as a member of inter-dimensional guards. When sudden spikes in fighting power propped up in Da Dong's old high school disrupting the KO ranking, he goes undercover to investigate... as a 28 year-old dropout repeating high school. His first order of business is to reestablish his authority inside the class of KO One. His behavior immediately clashes with the current leader, King. While the class looks on to see who would emerge victorious, the competition for leadership intensifies with new transfer students joining the fray. Watch drama online for free.