The book further covers the adventures of Jonah Lightfoot, a man stolen from his own world when he witnesses the 1883 eruption of Krakatoa. He and his unwitting companions cross the world of Amara, a vertical landscape where to fall from the world's surface is to die, or worse. They find a massive ocean, somehow held in place without the water falling into the abyss, and must then figure out a way to cross it. On their journey they discover the true nature of Amara; meet mermaids, forest spirits and shapeshifting creatures; cross paths with dragons both good and evil; delve into a world built of memory; and stumble across artifacts from Earth's past, present, and future.