The Gods of Mars
Edgar Rice Burroughs
John Carter returns to Mars after 10 years. He has a son who is completely grown up. Goes to rescue his wife and in the process discredits the religious beliefs and discovers the white and black men of mars. The white men were masquerading as the red men’s gods and the black men were masquerading as the white men’s gods. Overthrows the whole system. Ends with his wife being trapped in a prison that won’t open again for a year.