The Warlord of Mars (Unabridged‪)‬

At the conclusion of The Gods of Mars, John Carter's wife and two other women were locked in a slowly rotating prison attached to the Temple of the Sun, each of whose hundreds of cells are only open to the outside world once every year. John Carter must discover the secret of the Temple of the Sun to rescue the Holy Thern's daughter Phaidor, who has been imprisoned with Dejah Thoris and another Barsoomian princess, Thuvia of Ptarth. 

This is book three of Edgar Rice Burroughs' Barsoom series.