I know there are more books in the Barsoom series, but the end of the third book, The Warlords of Mars, feels like a pretty solid ending. I have the feeling that later books are going to feel tacked on, the author having been pressured to write them to continue a popular story beyond its range.
As with the earlier books, A Princess of Mars and The Gods of Mars, the story depends almost entirely on two things: that John Carter is a complete idiot who doesn't recognize clues when they fall in his lap, and that Providence tends to arrange the most remarkable coincidences every page to cause clues to fall in his lap.
In this third book, both of these factors started to strain past the point of being endearing and into the point of being annoying. John seems to get dumber every book -- perhaps it's all the blows to the head. Yet Providence, not content ensuring every random turn he makes leads the right way, every random person he meets happens to be of vital importance to the world or a relative, and every random encounter he has happens to be with someone who's just on the first line of a speech full of vital information, now goes to such extremes as to take a part in virtually every paragraph in parts of the book. I feel like Burroughs himself is getting tired of it, since he makes fun of it in character at one point, with Carter himself noting how kind Providence is to him (and how this explains why he doesn't bother to try to make decisions).
I have heard they're making a movie (and apparently that is a process that's been going on since the 1930s, the longest any movie has ever spent in development), and I wonder how they can do it without making such huge rewrites that we don't recognize the story. I can't imagine a modern audience could tolerate a hero so bafflingly thick-headed and idiotic. There's a particular scene, where he fights for a half hour or so thinking someone important to him is behind him despite her voice having been suddenly silenced a while back, and an enemy having been spotted mere moments earlier behind a tapestry, and never does he glance back and notice she's gone. In the middle of that fight someone even comes out and laughs at him about it and he still doesn't think to glance over his shoulder. He's doing things like this all the time.
Despite this, the story that spans the second and third books is surprisingly solid. As I wrote about the second book, the author has found lots more about Barsoom to flesh out without feeling like it's forced, like he's just cramming in stuff that should have been evident in the first book but wasn't. By the end of the third book, however, he has pretty much put himself in that situation. There's still room in Barsoom for a handful more things, hidden places, unknown secrets, previously unmentioned details, but it'll very soon start to feel like the world is crowded, like some of these things should have come up earlier, or like he's just stretching things out too far. So further books will probably start to lose their wonder since there's not really any room for a lot more of Barsoom to discover. But this far, it all fits together.
Unlike Gods of Mars, this book doesn't get too far off onto grandiose epic battles; everything is very personal like it was in the first book even when it's also epic in other ways. In fact, the author stages a big climactic final battle and then contrives to ensure it happens off camera by letting our hero face just two other people while it's happening far away, in a very nicely framed contrast.
Burroughs actually alludes to the possibility that the "heroine" (I hate to call her that, since she spends all her time being a damsel in distress) might pick up a sword and help out at one point, and yet she never manages to so much as slap anyone. The best she manages is to struggle in her chains and thus make a burden of herself to the villains. I know it's a modern sensibility, but I think the book would be improved, without having to sacrifice any of its feel, if just once she'd gotten to be the one to fight someone off, or save John, even if only from one of those acts of Providence. Burroughs sets the idea up but then doesn't act on it.
This book also does a good job of tying up the loose ends. It ends like Burroughs wanted it to be the end, or at least was planning for it. I have decided, therefore, to go read other things for a while. I'll come back and try the fourth book, but if it goes how I imagine it might, I won't feel compelled to finish it. I might just decide that this was the end.