The K2
One of the best action kdramas ever! Ji Changwook is honestly the King of Action. This was totally his prime where he acted well and looked disgustingly handsome (Am I being too obvious that he's one of my favourite actors ever ...LOL).
Moving on, the plot was engaging and tense. I think I was stressed 80% of the time. The action scenes were naturally awesome to watch. As for the romance, people preferred the male lead with the other female lead, which is insane to me. I think the main leads had great chemistry and looked cute together. Really enjoyed this series!