Byun Baekhyun gets bullied every day at school, he is the weak poor nerd who can’t defend himself. But this is every day, note the word, day. At night his personality takes a 180° change. Every night he rules the underworld as the leader of EXO-K the hottest and the most powerful gang in Seoul. He is heartless and ruthless and will kill in cold blood. But what happens if six new transfer students who call themselves EXO-M come to his school from China. Even worse what happens if they were a gang and the leader was a part of his past?