Book: The Gods of Mars
Author: Edgar Rice Burroughs
The Gods of Mars is the second book in Edgar Rice Burroughs' Barsoom series, set on a dying but not yet dead Mars; a Mars as was imagined prior to any exploratory vessels reaching the planet. Some of the elements in this book were referenced in the film John Carter.
At the end of A Princess of Mars, John Carter was unwillingly transported back to Earth. Ten years later, he is transported back to Barsoom. This return to Barsoom coincided with Carter's apparent death on Earth, at the beginning of the previous book when Burroughs was summoned to meet his relative, John Carter, only to find he had just died.
There is a difference in the John Carter in this book from the one in A Princess of Mars. Rather than merely being an Earthman transported to Barsoom whose strength evolved to deal with Earth's greater gravity game him an advantage, he now seems somewhat superhuman - not merely a man, but one who has lived for decades prior to his first adventures on Mars and never aged, nor can he even remember his own age or his childhood.
The book is in many ways similar to A Princess of Mars; Carter spends much of his time travelling across Barsoom so that he can once again be with his beloved Dejah Thoris, and see if their child had hatched (because Martians are all born from eggs), being snatched back to Earth just prior to the eggs five year incubation being concluded as he attempted to save the planet after the atmosphere plant had been shut down.
Carter along the way meets up again with old comrades such as Tars Tarkas, the green Martian and Jeddak of the Tharks. He also meets members of two of the older races of Mars; the white Martians, or Therns, and the black pirates from the inner moon. Both these races predate the red Martians of which Dejah Thoris is a member, the red Martians being a crossbreed from the white and black races and the extinct yellow race after Barsoom started to die.
Although A Princess of Mars does function as a stand alone novel, The Gods of Mars does not. It is definitely helpful to have read the first book, and the story is not finished in this book but continues in The Warlord of Mars. The book is again more sword & sorcery than science fiction, although there are some science fiction overtones, such as the propulsion of their sky vessels, guns and the plant that maintains the remaining atmosphere of Barsoom. There is a bit more of a plot than the last novel, although the novel is not really plot driven. This is not great literature but fun, if dated, adventure fiction.