Daisy Kim is a girl from a poor family but has an unrivaled sense of optimism. It all comes to a head when she is forced to transfer schools from Texas to Seoul. There she meets the infamous group of nine astonishingly good looking and rich boys who are known as NCT 127. The group's leader is Lee Taeyong, who is a spoiled heir to a world-leading conglomerate. He is joined by mysterious and breathlessly handsome Jeong Jaehyun. Taeyong enjoys the thrill of making Daisy's life miserable. Gradually, Taeyong falls deeply in love with her, only to realize that she is already in love with one of his best friends.