Hakyeon's always thought himself as a level-headed, serious investigator, who doesn't break the rules for anybody and gets the crime solved quickly and quietly. But when he encounters Taekwoon, all his principles fly out of the window. Soon, he finds himself caught up in a tangled web of revenge, acceptance, and forgiveness. Only Taekwoon knows how to unravel him.
Basically, Leo's a criminal and N is his investigating officer.