Divers stumble upon an immortal jellyfish in the Caribbean Sea, hinting at the possibility of immortality for humanity. This leads to the development of Harmonia, a daily pill that promises youthful looks. Unfortunately, a musician experiences a deadly side effect on live TV as they rapidly age and die. Junam, trapped on Nakwon Island with his family, church volunteers, close island friends, and a limited supply of Harmonia, must devise a plan to escape alive.