[ THE CLAN: X ] Yoo Kihyun, the leader of South Korea's biggest gang, has returned to Seoul after 7 years. On the flight back, he meets a handsome flight attendant, Son Hyunwoo, and develops a liking for him. But when he receives a call from an old nemesis, he gets the biggest shock of his life. Is Son Hyunwoo really as simple as he seems?  Read on to find out.