I've finished reading The Dark Tower septology. It was a lot of work to avoid the spoilers, but I'm glad I did. The journey was long and strange. Not everything was filled in, not all the prophecies were fulfilled. Some events exceeded my expectations, some ended unsatisfied.
But the important thing I think is how it ended.
HERE THERE BE SPOILERS FOR THE DARK TOWER.
At the end we wrap up the whole metafiction theme. Stephen King has been introduced, his near-fatal accident has been made an integral part of the plot, and if we haven't realized by now that this is a story about a story, we've been smoking too much devil-grass. So it should come as no surprise that the ending of the saga takes a "Never-Ending Story" type turn. Right before the revelation, King warns us to turn back, to embrace the happy reunion of the three other main characters as the ending, rather than the impending coda.
Of course, me being obsessive-compulsive, has to read on. I got this far, I can't go back. I originally thought he was going to end it with Roland just entering the Dark Tower and not showing us what's inside. But there are stairs and he does climb to the top, finding a room every 19 steps. Inside each progressive room is a moment of his life, from birth, to training, to exile, to quest, to the events in the books, and finally comes to the last door of the present. Like all other doors in this story this one is marked with words - "Roland". (Here's the big spoiler): He opens the door, and discovers... the very first scene of the first book. With horror, he realizes that ka (fate/destiny) really is a wheel. It is cyclic, and he is doomed to repeat the events of the seven books over and over again. As he is sucked in to the world, and begins to forget all that has happened in the past, the end is the beginning. "The man in black fled across the desert and the gunslinger followed."
With this dismal, despairing ending, King reminds he's a horror writer at heart, despite the Dark Tower books being a blend of science fiction, fantasy, and supernatural. There has been no Cujos, no langoliers or tommyknockers. No Jack Torrance, and no Carrie White. There have been monsters, but they've mostly been obstacles, and not many have inspired the same terror as It and Pet Sematary. In fact, if King hadn't added that twist, I wouldn't have felt any visceral emotion from these stories. Kinda reminded me of Saw. But King is not without mercy, and adds one small element of hope - the horn of Gilead, which he had not possessed at the beginning of the books, implies that the events can be changed.
However, that's a small dot in a big canvas, and I think the reader is meant to infer that Roland has been doing this forever, over and over, climbing to the Tower and falling back, in a Sisyphusian effort, both not achieving and achieving his goal (of preventing the unmaking of existence). I took it a step further and interpret that every time someone reads the Dark Tower books, Roland begins his quest again. No evidence, but its fun to think about because of the metafiction and the 'never-ending story' motifs. If you can make this revelation, the Dark Tower series just becomes that much more epic, and you feel more like part of the story. You are not only accompanying Roland on his journey, you are causing it. When I realized that, I felt partially responsible for his plight, his fate, because I picked up the book and started him, like moving a playing piece (like Jumanji). How ironic that one would start the journey over again, only to leave it for someone else to repeat.