Kaizaki Arata is a 27-year-old unemployed man who, after quitting his last job after three months, has failed every interview since. Enter Yoake Ryou; representative of the ReLIFE Organization. He offers Kaizaki a pill that changes his appearance to that of his 17-year-old self; thus, Kaizaki becomes the subject of a one-year experiment in which he begins his life as a third year high school student once again.