In the last days of the twenty-first century, sea creatures swim through the ruins of London. Trapped in the abyss, humankind wavers between fear and hope--fear of what lurks in the depths around them, and hope that they might one day find a way back to the surface. When sixteen-year-old submersible racer Leyla McQueen is chosen to participate in the prestigious annual marathon, she sees an opportunity to save her father, who has been arrested on...