The novel concludes the trilogy begun with “The Daughter of a Thousand Jeddaks” and “Gods of Mars.” John Carter manages to restore power in Helium-Tardos Mors and Mors Kayak, and he sets off for the valley of Issa. The time is drawing near for the opening of the temple where Faydora—the daughter of Matai Shang—Dejah Thoris, and Tuvia P’tarsa are imprisoned. However, the captives were seized by Matai Shang and the leader of the black Martians, Turid, who fled to the state of Kaol—the stronghold of an ancient religion. After John Carter and Tuv’an DIn—ruler of P’tarsa and Tuvia’s father—manage to expose the invaders, they flee to Martian Arctic (Okar), where greenhouse cities of the Yellow race are located. With great difficulty, John Carter overcomes all obstacles and reunites with his family, meanwhile uniting peoples of different races. After returning to Helium, John Carter is brought before the tribunal of the 31 rulers of Mars (including Tars Tarkas, Tardos Mors, Mors Kayak, Tuv’an Din, and Talu—the ruler of the Yellow Martians), where he is proclaimed supreme ruler of all Mars.