Although Rogue Queen is the only story that takes place on Ormazd, the various tales are united by the theme of technologically advanced Earthmen visiting planets whose cultures approximate the technology of Earth's Bronze Age. Visitors to such planets are forbidden to introduce advanced technology into the backward cultures but nearly always do anyway, just as the machete is introduced to the Avtini. The books are brimful of unusual social customs and excitement.

Other tides are: The Continent Makers and Other Tales of the Viagens (1953), short stories; Cosmic'Manhunt(1954), novel (also published as A Planet Called Krishna and as The Queen of Zamba); The Tower of Zanid (1958), novel; The Search for Zei (1962), novel (also published as The Floating Continent); The Hand of Zei (1963), novel; and The Hostage of Zir (1977) novel.