Stephen King’s literary magnum opus took over 20 years to complete, and currently spans seven novels (with an eighth supposedly on the way). It also spawned a series of prequel comic books, which are set to wrap up next month. Because of the long gap between the first and final novels, King’s ideologies and assumptions about his own world don’t remain consistent from beginning to end. This also causes the series to defy a rigidly-defined genre, swaying between sci-fi, fantasy, western, and horror (to name a few).
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The world in which the story takes place also changes over time, in whole and in part. That is, a multiverse exists, so the series sees the characters move between different worlds from time to time. Also, the primary world, known as “All-World”, undergoes dramatic changes itself which affect the story. Geographically, All-World is divided into three parts, known as “In-World”, “Mid-World”, and “End-World”, with the characters traversing from In-World to End-World. It’s seen as a definite descent into decay, with the past memory of In-World being harmonious and beautiful, the future goal of End-World being barren and bleak, and the present state of Mid-World (where most of the series takes place) being in the process of falling apart by the time the first novel starts (“the world has moved on”, as they say).
It’s worthwhile to note how the tone and morality of King’s prose mirrors the journey portrayed in the novels. While the value placed on combat (particularly with revolvers) is maintained throughout, the first novel carries assumptions of clearly-defined Good vs. Evil (with Evil being the more powerful), and a single, focused goal to pursue (the Tower itself). As the series progresses, this goal is sidetracked by the addition of more characters and the realization that nobody really knows what’s in the Tower or why it’s worth pursuing. Furthermore, King came to believe more in the banality of Evil in his later years, and the supposed “Big Bads” of the series ultimately become ineffective. It’s not even that Good and Evil enter a gray area; it’s more that Good and Evil simply become irrelevant concepts.
This constantly evolving environment is somewhat justified by the multiple worlds the characters inhabit, since the rules governing each are understandably different not only from each other, but from our own. This allows King to get away with writing about vampires, mutants, sentient robots, time travel, psychics, magic, etc., without deviating from his core story. He also heavily suggests that the worlds of other authors (including Isaac Asimov’s robots, the legend of King Arthur, and Harry Potter, among others) coexist within the multiverse of the Dark Tower, expanding the boundaries of his world beyond his own imagination. Furthermore, King labels one of the worlds as “Keystone Earth”, and makes it clear that time can only run forward in that world, so that it’s ostensibly a representation of the “real” world.
It’s also in the Keystone world that King inserts a fictionalized version of himself into the story, sparking an unexpected turn in the perception of his created world. He displays his awareness of fictional stories taking on lives of their own, as the characters of the 6th book interact with a past Stephen King who had just written the 1st book. Real life events (e.g., King’s near-death car accident in ’99) become important plot points, and the series begins to break the fourth wall, with characters realizing their world only exists because King wrote it, and King saving the characters with named deus ex machinas.
The later books, thus, become interesting self-observational takes on King’s own relationship with his written works, bringing the series full circle in a significant way. As a whole, the series also stands as a centerpoint to many of King’s other books, which relate to the Dark Tower in at least some way. Quite literally, then, the Dark Tower holds together the fabric of Stephen King’s literary realities.