After five years of suppressed affections, Taiju Ooki, a high school student, is finally ready to reveal his feelings for Yuzuriha Ogawa. However, just as Taiju begins his confession, a bright green light blasts the Earth, terrifying humans everywhere and turning every single human into stone. Several millennia later, Taiju awakens to discover that the contemporary world has vanished, as nature has grown in the years that humans has been dormant. Taiju comes into one other live human among a stone world of statues: his science-loving friend Senkuu, who has been active for a few months. Taiju discovers that Senkuu has devised a vast plan to resurrect civilisation through science. Taiju's muscle and Senkuu's wits combine to make a powerful alliance, and they quickly discover a way to work together.