Edgar Pacey is alone in a world without loneliness. His home, Vertical City, a gargantuan skyscraper on the island of Tristan da Cunha, is claustrophobically packed with the last remnants of the human race. Edgar, a carbon miner and resident of the underground, awkwardly navigates his days without privacy or solitude. He often wonders - to the indifference or confusion of those around him - if their way of life is normal? But then, Edgar's quick thinking during a seemingly freak mining accident gains him widespread recognition; his newfound fame opening previously unexplored parts of the city - the revered upper floors. Guided partly by this twist of fate, partly by a selfish desire to satisfy his own misgivings, Edgar uses this freedom to search for a flaw in their esteemed city, inadvertently leading him to the frightening cost of humanity's continued survival. Risking his own life, Edgar will have to force a complacent society to reevaluate itself, with repercussions that could raze their colossal tower, and humanity's last refuge, to the ground.