Lee Mingi is a genius rocker, as well as leader, vocalist, and guitarist of a rock band called Ex-So (Excellent Souls), that he founded together with drummer Han Gijoon. The cynical Kang Hyeok is the keyboardist of the band, but also a medical school student who is from a family of doctors for many generations. The two will be involved in a love triangle with the lead female. Meanwhile, Yoo Hancheol is the bass guitarist.