After five years of harboring feelings for Yuzuriha Ogawa, high-schooler Taiju Ooki is ready to confess his love when a blinding green light strikes Earth, petrifying humanity into stone. Millennia later, Taiju awakens to a world where nature has overtaken civilization. He meets Senkuu, a science enthusiast who has spent months working on a plan to revive humanity using science. Combining Taiju's strength with Senkuu's intellect, they uncover a way to bring people back. However, Senkuu's vision is challenged by new ideologies, and the mysterious cause of humanity’s petrification remains a looming question.