Rebecca West frequented the borderlands of human experience, reporting on the very best and worst that humanity could achieve. She was a respected literary critic, an authority on the beauty of man's creations, and a journalist who reported on the horrors of two world wars. Unable to accept any dogmatic explanation of the presence of evil in man and in the world, she embarked on a private investigation of human nature. The fruits of West's quest, her copious writings, are naturally interstitial, spilling into the realms of politics, religion, culture, history, and art. Even West's fiction crosses traditional boundaries, ranging through genres in search of truth. The unfinished trilogy she called A Saga of the Century – The Fountain Overflows, This Real Night, and Cousin Rosamund – defies all attempts at conventional categorization.

In literature, interstitiality is often a diagnosis of exclusion: a novel or story is neither this nor that, not fantasy, not magical realism, not the fantastic, but not realistic either. However, an excellent work of interstitial fiction must embody a positive definition as well. It must use elements from various genres to create something unique; the unusual choices made by the author must be purposeful rather than accidental. When fulfilled with style and grace, these special requirements create an exceptionally close relationship between story and genre, content and form. All paths are open, and any technique that serves the purpose of the story may be used. In this way, the structure of the work bends to accommodate the author's intent. Interstitial fiction conveys meaning through both the story and its unique form, just as an unusually shaped poem expresses meaning though its words and their placement on the page. The shape of the fictional narrative, defined by the singular combination of genre elements that the author has chosen, inevitably mirrors the themes of the story. In the case of West's cycle, a distinctive blend of fantasy and realism is used to express West's personal philosophy.

West needed an original framework in which to explore her beliefs. She was unable to reconcile her feminist ideology with the bias she saw as inherent in the Christian church, and disagreed with Christian views of sin and suffering (Glendinnig 210, 211). She investigated Judaism and studied ancient myths, but she was never able to accept the dogma of any organized religion. She wrote in 1952, four years before the publication of The Fountain Overflows, "I hope I am working the way to the truth through my writing" (Goodness 188). Certainly, A Saga of the Century is West's most complex and most personal exploration of the dual nature of humanity. Its interstitial form enables West to illuminate spiritual values using supernatural occurrences and mystical destinies, while also insisting that the novel is set in the real world, and the lessons it teaches are relevant to the readers.

Previous critics, products of their time, have failed to consider the possibility of novels existing between genres, and have therefore oversimplified the implications of the supernatural in A Saga of the Century. Orville Prescott, reviewing A Fountain Overflows after its publication in 1956, notes only that, "Such Gothic fantasy seems oddly out of place in a novel so basically realistic" (Prescott). Later critics have framed the genre debate as a choice between realism and fantasy, hinging on whether the supernatural occurrences in the novels are real or imagined. Harold Orel concludes that the events are unquestionably real, placing the novel into the category of fantasy (and denying West's deliberate introduction of doubt) (Orel 152). Peter Wolfe dismisses the events as figments of Rose's imagination, classifying the novel as realistic (and robbing the supernatural events of their significance for the real world) (Wolfe 112). A more nuanced reading suggests that West took pains to ensure that that her novels were neither fantasy nor realism, and that the supernatural events within them cannot be definitively labeled either real or unreal.

West clearly meant to set her novels in the real world. In an article on Charlotte Bronte that expresses a certain disapproval of fantasy, West writes that a true artist "sets out to explore reality" ("Charlotte Bronte" 429). In her plan for A Saga of the Century, published in an afterword to the unfinished Cousin Rosamund, West writes that Rose's story will take place against the backdrop of a time when "the world was passing through a phase of disintegration" (Cousin 295). At every turn, West points out that Rose's experience is shaped by her era. An unpleasant encounter in Cousin Rosamund is not merely with two young men, but with "two of those young men, to be found at all parties in that decade, who had got very drunk because they felt they were going to be killed in the next war" (Cousin 10). Political history permeates the cycle, constructing grand destinies for Rose's cousin Rosamund and her younger brother Richard Quinn.

Another technique West uses to anchor her novels in the real world is a continual de-emphasis of the supernatural itself. After defeating a poltergeist, Rose explains to her new-found cousin Rosamund that what strikes her as really strange is that it is impolite to suck on a piece of chocolate, but it is perfectly acceptable to dip buttered bread into an egg. Rosamund agrees, "Those are the things I call really queer" (Fountain 124). Rose's nonchalance keeps her story focused on her new relationship with Rosamund, rather than the horror of the poltergeist. The supernatural occurrences in A Saga of the Century are a commentary on reality, not an escape from it.

Most novels that integrate elements of fantasy into a realistic world belong to the genres of magical realism or the fantastic. The theorist Amaryll Beatrice Chanady provides a framework for comparing these two genres that is useful for understanding West's interstitial work as well. Building on the work of Tsvetan Todorov, Chanady describes how two levels of reality clash in the fantastic, and harmonize in magical realism. According to Todorov, the reader of a fantastic story is unable to decide whether supernatural events actually occurred or not. The reader hesitates between two explanations of ambiguous events; one theory is rational but seems complex and improbable, while the other theory relies on magic but is elegantly simple (Chanady 3). Chanady completes this theory by noting the features of a fantastic text that produce the reader's hesitation. In her opinion, a fantastic story contains two conflicting levels of reality, one that operates according to the principles of reason, and another that is magical and inexplicable (Chanady 4). The unresolvable conflict inherent in the presence of two conflicting codes creates the reader's hesitation (Chanady 12).

Two views of reality are also present in magical realism, but in this genre the tension between supernatural events and a realistic world is resolved. The main character establishes a mystical world view by his or her unquestioning acceptance of the supernatural, and the author establishes a rational world view by setting the story in a modern world and adopting a logical and educated tone (Chanady 21-23). The narrator refrains from drawing attention to the strangeness of supernatural events, which are embedded in a system of beliefs or superstitions held by a certain population, often the native inhabitants of Latin America (Chanady 149). Since the characters are not disconcerted by the coexistence of two levels of reality, the reader can also accept the contradictory views (Chanady 21-23). Chanady explains:

By presenting various different perceptions of reality... the narrator allows us to see dimensions of reality of which we are not normally aware. The supernatural....is juxtaposed with everyday reality in order to create a more complete picture of the world. [It is] the means to an end, and this is the penetration of the mystery of reality (27).

West shares the goal of magical realism that Chanady describes, but her methods differ greatly. Whereas magical realism depicts complete acceptance of the supernatural (Chanady 149), West uses doubt to reach the same ends, placing her novels between genres.

In writing an interstitial story, the author must tear down the walls between genres, and pluck from each familiar constellation of techniques exactly those methods and elements which will best shape the narrative. In A Saga of the Century West does exactly that, blending elements of realism and fantasy, and using techniques culled from the fantastic and magical realism. The trilogy in some ways resembles the best Victorian novels, with their casts of humorously faulty supporting characters, their thick but witty prose, and their depiction of children struggling with poverty. The first book, The Fountain Overflows, is set near the turn of the twentieth century; its narrator, Rose, is a version of West herself as a child, though she is a pianist and her ambitions are musical rather than literary. Rose's house in the suburbs of London is the house of West's earliest memories, and Rose's anxious mother and genius yet unreliable father are fictionalized versions of West's own parents (Glendinning 16-17). Against this familiar backdrop, West unfolds the spiritual dilemmas that pervaded her life. She uses two elements of fantasy – supernatural events and mystical destinies – to explore two essential mysteries: the eternal battle between good and evil, and the coexistence of free will and destiny. To accomplish this, she crosses the boundaries between genres to create a truly original fictional world.

One lesson Rose must learn as she grows is to accept the challenges of the present and resist the twin temptations of living in the past or relying on the future. To demonstrate this maxim, West realigns the boundaries of the "real" world, deliberately choosing to cross genres. She writes Rose's first magical experience--the appearance of phantom horses in the empty stable during Rose's first night in her new home – in the style of the fantastic. West's ambiguous language makes it impossible for the reader to determine whether Rose and her mother have seen an apparition or whether Rose has been dreaming. The line between sleep and waking is blurred as soon as Rose lies down; her father, kissing her good night, becomes "a person in a dream" (Fountain 59). Rose writes that she "awakened" to the sound of horses' hooves, but that she hadn't "realized that I was awake" until a paragraph later (Fountain 59). The repetition of the word "awake" makes it difficult to pinpoint the precise moment of Rose's awakening, and therefore to confirm that she is in fact awake. The horses themselves are ambiguous, present yet not present. Rose remembers that "the mangers... held nothing but dust and shadows....But in this emptiness four horses slept and dreamed" (Fountain 61). Rose is still wondering if she has seen the phantom horses, or has dreamt them, years later (Fountain 189). By carefully balancing the indications that Rose is asleep and awake, West makes it impossible for the reader to determine whether a supernatural event occurred or not. This is the fantastic style; yet, in this interstitial work, the scene serves a purpose foreign to the fantastic.

Instead of creating irreconcilable tension, the encounter with the phantom horses tells Rose that she must leave the past behind, something that she will find difficult as she approaches adulthood. Rose says that she and Mary are forced to leave the site of their idealized childhood because, "Our house could have seduced us into the practice of magic; we might have recreated the past and inhumed ourselves in it" (Cousin 1). In Cousin Rosamund, Rose must let go of the past in order to build a life for herself outside of the shadow of her parents, just as she and Clare let the horses from the past fade away into memory. Only an interstitial work could use magic combined with fantastic-style doubt to teach a lesson valid in the real world Rose inhabits. It is the real world West means to portray: the tragedies of the narrator Rose are the tragedies of her generation; the loss of her brother in the First World War is the expression of a national grief; the downfall of her father parallels the collapse of the old world order. The interstitial form mirrors the unique story that West wants to tell.

West uses doubt in the manner of the fantastic, but she creates a unified world in the manner of magical realism. In these novels, the minutia of poverty, the relations of a family, the history of a nation, and the workings of the soul seamlessly combine. The realistic and the unrealistic work together to depict a world that is both recognizable and spiritual. Aunt Lily's pork pie is "magic" (Fountain 268), and the reason why one lilac blooms before another is a profound mystery (Fountain 306). Details of this kind blend the heavily significant elements of fantasy into the world of the everyday. Rose pauses in This Real Night to explain her motive for recounting minute, quotidian details as well as mystical events:

I am writing all this down in full knowledge that it will not now seem important, for the reason that that is just what marks off that past from our present. . .in life we were not divided. Life itself was not divided (Real Night 160).

In a world without divisions, a line between the realistic and the unrealistic cannot be drawn.

West's characters inhabit a space – difficult for modern readers to accept, but more natural for those who lived early in the twentieth century – that is in itself liminal. It is the gap between the modern, adult belief in science and the old, nursery belief in superstition, where both codes – both realities – are given a degree of credence. As a child, Rose is still discovering the rules that govern her world, but even the adults of her time move between cosmologies. Her mother Clare and the maid Kate are both experts on the supernatural, but they can still approach the unsolvable puzzle of free will and destiny from a modern perspective. When they argue, destiny appears as heredity modified by environment and free will is referred to as choice (This 27). West uses an interstitial approach to depict a time when respectable, rational people attended séances and hired mediums.

Though the modern impulse is to label the supernatural events real or unreal (and the novels realism or fantasy), within the narrative these events exist on a continuum, rather than in separate spheres. Thanks to this essential unity, the meaning of one encounter with the supernatural can be applied to an entire lifetime of ordinary events. Phantom horses can teach Rose to face the present; faith in Rosamund's magical destiny can lead to faith in the goodness of humanity. Lessons taught by fantasy remain valid in a realistic world, since all of the aspects of this world are connected. Though all this might be said of an example of magical realism, only in an interstitial work could this unity be created by doubt, rather than acceptance. Doubt fosters tension; it highlights the incompatibility of two views of reality, ordinarily tearing a fictional world in two. Yet in A Saga of the Century, doubt creates a world where the characters can struggle with the incompatible elements of the universe just as their real cohorts did, a world more made more whole by the inclusion of the characters' skepticism. In these novels, issues of destiny, foreknowledge, magic, good, and evil, are so intertwined with the intensely realistic domestic and financial problems of Rose's family, that belief in the supernatural seems no more outrageous than religious faith.

In choosing an interstitial approach, Rebecca West creates not a fantasy world, but a mystical vision – a religion, in which good is more important than God. By emphasizing the divided nature of humanity in her novels, West may have intended to create a theology similar to that of Manicheism, a Gnostic school of thought. West saw duality in everything, and wrote that a human being is "an amalgam of the will to live and the will to die" (Glendinning 212). She was fascinated by a Manichean myth that relates how Satan, the ruler of the kingdom of darkness, invades the kingdom of light using a mixture of darkness and light as his weapon. He succeeds in corrupting the light, contaminating all matter. Thus, the "material world exists so that man may fight to separate the darkness from the light in himself and so be united with God" (Glendinning 211). West refers to examples of purity, such as Rosamund and Richard Quin, as "children of light" (Fountain 165). Rose is amazed as Rosamund's "golden simplicity dispelled Queenie's blackness" (Fountain 308). Queenie is a murderess – she killed her husband – and Rosamund's light is the only thing that can keep her darkness from contaminating Rose's home. In West's world, some people have escaped contamination by the dark and can therefore fight the darkness in others. Most fight the darkness in themselves.

Despite its religious overtones, A Saga of the Century is in no way guilty of proselytizing. West writes that she would never try to convince another person of her beliefs, because this would discourage the person from seeking his or her own revelation (My Religion 21). West was convinced that true insight into the nature of God and reality couldn't be contained in a religious creed. Dogmas are understood by the intellect, while mystical intuition must enter into the "core of our being, which lies far beneath the level of consciousness" (I Believe 372). After all of the lessons of her supernatural experiences are unpacked and tabulated, Rose herself must decide to believe. It makes little difference that West has included supernatural manifestations and magical destinies among the ideas that Rose will have to accept, because all religions require faith. The sense of uncertainty, of borders crossed, of interstitiality that pervades the trilogy confirms that the essential mysteries of our existence can never be fully penetrated. Where knowledge falters, acceptance of life's incomprehensibility must begin.