Jeon Jung Kook and Jeon Jung Hyun are twins who are sent to USA for dance training. After completing their training, they return to Seoul; and immediately Jung Hyun gets to be in BTS as it's newest member. Jungkook is extremely happy for his brother who isn't happy at all. As a result, Jung Hyun runs away. And finally Jungkook ends up disguising as his brother for the sake of his brother's future. But... Will BTS accept him?