A hot-blooded prosecutor is murdered when he gets entangled in an investigation around a corrupt politician. He gets sent back in time to when he was 18 years old, and he prepares to take down his enemy.

When Kim Hee-Woo (Lee Joon-Gi) was a high school student, his academic grades ranked at the bottom of his school. Through hard work, Kim Hee-Woo entered a university and eventually passed the bar exam. He now works as an enthusiastic prosecutor. While he is investigates possible corruption related to a politician named Jo Tae-Seob (Lee Kyoung-Young), he gets killed by an unidentified men. But, Kim Hee-Woo wakes up and finds himself alive again.—AsianWiki