This is the lives of two teenage girls who just happen to be the daughters of secret agents that work for the blue house. How will leechul and youngnam react when the are told they will have to go undercover in Hanlim arts high school! Also what will happen when they end up knowing the 7 kingkas of the school(BTS) have a big secret if there own and how will they react when they find out they are working on the same case... Will they fall in love or will things take a turn for the worst!!.....