16-year-old Jang Ji Gu (Seo Young Joo) takes care of his ill grandfather, while he hangs out with other troubled kids. He was abandoned by his parents at an early age. After another run in with the law, Jang Ji Gu is sent to a detention center. One day, Jang Ji Gu hears that his mother Hyo Seung (Lee Jung Hyun) has come for him at the detention center. Hyo Seung had Jang Ji Gu at the age of 17 and gave him up soon after birth. Can they repair their relationship?