After the Great Catastrophe, three additional intelligent races appeared on the planet. Each race took its place in the new world: people remained to live in the northern lands, the coasts of the continents and islands were inhabited by merpeople, the orangs occupied the jungles and forests of warm latitudes, and the arid lands and deserts remained to the people of the drags. Just as after the Great Catastrophe, children of other races suddenly began to be born to people, so many centuries later, human children began to be born to different nations. The world was changing again and human scientists are trying to find the answer to this phenomenon. Tuok, a man born into an Orang family, upon reaching adulthood, faced the choice of remaining among his people, but not being able to find a family, or going to the northern lands among the people and trying to find his place there. He chooses the second option and, with a trade caravan of dredges, sets off on a long journey, in which many adventures await him and a meeting with a group of scientists from the human people. This meeting changes his plans.