The notion of alternate universes lives in a strange place in popular imagination. It is used by popular movie franchises, debated by science and the topic of the occasional joke. The multiple universes of C.S. Lewis’ Chronicles of Narnia predate most of these interpretations and their presence is often forgotten within the wider image of Narnia. This image was somewhat reworked in Lev Grossman’s Narnia inspired Magicians books but the utilization of the multiverse remained quite similar. These books demonstrate the limitations of the notion of alternate universes because the readers are only able to focus on these worlds one at a time. So, in these conceptions the multiverse becomes a kind of back closet where characters and ideas can be shoved for later use before being pulled out at the appropriate moment. Both Lewis and Grossman us this strategy to great affect with good writing making the movement in and out of the multiverse feel smooth and blended with the more singular world of their stories.
C.S. Lewis used a kind of hub for his multiverse in the form of the wood between the worlds which allowed him to contextualize the idea of many worlds for readers through the visual metaphor of the many pools. This is not a true alternate world to the human world and Narnia, it is an in between space, a liminal space, that allows for transition between more developed ones. The characters in the Narnia books very rarely spend any time in the wood between worlds, and when they do any conflict is focused on ways to move away from the in between space. Lev Grossman continues with this strategy as his stone city between worlds uses never ending fountains for the many possible universes. The whole of the world building in the Magicians is heavily tied to that of the Narnia books but this use of liminal space makes it especially clear with the notion of water as the barrier between worlds. Although in later books the stone city is a point of conflict it is limited and out of sight because the powers of the protagonists do not operate in this in between space. Collectively all of these limits that both Lewis and Grossman employ make the travel between universes difficult, and so impractical that the reader is not surprised when travel between universes happens only with a few places rather than the infinite variety the notion of the multiverse says is possible.
In this model of the multiverse all those other worlds are the back closet that characters, plots, and problems can be pulled out of. Jadis, the soon to be White Witch, comes from a dead alternate world that for all intents and purposes exists only briefly in The Magician’s Nephew. Lewis doesn’t need to develop Jadis’ world because he doesn’t intend to use it beyond being a source for evil in the otherwise idyllic Narnia. Alternate universes are simply a way of bringing in elements that couldn’t probably originate inside Narnia itself just as the children must come from our world rather than simply being citizens of Narnia. Grossman reverses this paradigm somewhat as he tends to send his characters away into alternate worlds to explain their absence rather than pulling things out of them. When not needed for the main plot various characters head off into different worlds to attempt to find Tolkien’s elves or have other kinds of out of sight adventures. Just like how children pile messes into closets when told to clean their room, Grossman sends his extraneous characters out into the multiverse.
This strategy works, the reading of these books doesn’t feel like the multiverse is contrived because really the reader can only care about a limited number of worlds anyway. It makes more sense within the context of the story for the characters to be going on some other adventure, or the evil sorceress to have come from some darker world, but those are not places that the reader actually cares about within the context of the plot. The magical worlds that both Grossman and Lewis have at the centre of their stories are developed enough to hold the attention away from all the other theoretical worlds. This is the strength of the multiverse as it is used in these fantasy books, there is no need to remember or care about alternate worlds until the precise moment the author decides to open that closet door. There is none of the confusion about timelines and such that characterize stories that are more dependent on the alternate universe theory as it is scene in DC or Marvel films.
Good world building isn’t just about depth, the illusion of complexity is often just as effective so long as the author is aware of how their readers will focus. C.S. Lewis was writing before the average reader would have been aware of alternate universes but his blueprint use of many worlds has had long lasting effect. The wood between the worlds is an archetypal liminal space from which he can pull characters and conflicts as necessary. Lev Grossman continued to develop this work in his Magicians books with more contemporary sensibilities through references to pop culture while still retaining the limited use of the multiverse. In the end readers are going to focus on the world that characters inhabit in the moment and the ability to move between an infinite number of worlds is less important than the judicious use of just a few.