When the harsh realities of adulthood and workplace harassment tarnish childhood aspirations, the desire to rewind time and rectify past decisions becomes a tempting prospect. Enter Arata Kaizaki, a 27-year-old at a crossroads, offered a unique chance to reset his life. Recruited by Ryou Yoake from the ReLife Research Institute after a fateful encounter, Arata embarks on an experimental journey. Through a miraculous transformation, Arata regresses to his 17-year-old self, tasked with reliving high school for a year to rediscover himself and reintegrate into society. Promised a career opportunity at the experiment's end, Arata, desperate for a fresh start, reluctantly agrees. Yet, armed with adult wisdom but lacking in current academic prowess, Arata faces the daunting challenge of navigating the complexities of high school life once again.