Tschai is a planet orbiting the star Carina 4269, 212 light-years from Earth. It is populated by various sentient alien species. The native Pnume have been subjected to invasions by three species. In addition, there are humans, captured and brought to the planet long ago by one of the spacefaring species; some of them live as slaves or servants of each of the alien races, while others have managed to create their own societies. Each of the four novels relates Reith's adventures with one of the species, and is named after that species. In order, the books are:
