While the upcoming John Carter of Mars film has been described as an adaptation of the first novel only, the appearance in the cast list of the character Matai Shang, ruler of the godlike Therns suggests otherwise, as Shang and his merry band of Therns dont show up until the second and third novels. And the Civil War colonel who comes into conflict with Carter corresponds to nothing in the books whatsoever.
I fear that the faithful movie adaptation that fans have spent nearly a hundred years waiting for (admittedly treating fans as a collective of variable composition) is not on the way.
But wait, it gets worse. Actor interviews (see here and here) reveal that the Therns are beings like Olympian gods who travel round keeping order in the Universe (they do no such thing in the books) and that the aforementioned Matai Shang (a fairly minor character in the books its his daughter Phaidor whos important) will be John Carters nemesis and a shapeshifter who can adapt into anything.
Talk about missing the point! The whole idea of the Therns is that theyre false gods theyre just ordinary human beings who have set themselves up as gods. Giving them supernatural powers of shapeshifting and starhopping defeats their literary purpose. Burroughs structured Barsoomian society so that the religion of the red and green Martians would be a hoax perpetrated by the white Martians (i.e., the Therns), the religion of the white Martians would be a hoax perpetrated by the black Martians, and the religion of the black Martians would in turn be a hoax perpetrated by their own rulers. (Burroughs, as you may have guessed by now, was not a fan of religion; see also Savage Pellucidar and The Return of Tarzan.) If the Therns are now going to have magical powers, or be aliens with more advanced technology, or whatever it is thats being planned here, then the story that Burroughs actually wrote is evidently being fairly thoroughly jettisoned.
My enthusiasm for this movie is rapidly dropping.