The appearance of Cloud Atlas not only on the bestseller lists, but also as one of the 10 books chosen for the Richard and Judy Book Club says something about the contemporary reader's willingness to accept what would once have been thought experimental narrative technique. For Mitchell's novel arranges narratives not just set in different times, but also written in different genres. No sooner has a reader become used to the expectations fostered by one kind of story, than there is a shift to a narrative world with new rules.
The linking of distinct narratives set in different times is not unprecedented. Michael Cunningham's The Hours, for instance, had three parallel lines of narrative set in, respectively, the 1920s, the 40s and the 90s. The gaps between the narratives in Iain Pears's mystery The Dream of Scipio were more dizzying, spanning the fifth, 14th and 20th centuries. Generic shifts are more unusual than temporal ones. I cannot think of another novel that is so formally divided up between genres: six narratives, each of which could be extracted from a completely different kind of novel.
First there is "The Pacific Journal of Adam Ewing". It is a fictional 19th-century diary, in mildly antique prose, but also a voyage narrative that recalls Melville's tales of the South Seas. It breaks off in mid-sentence after 36 pages in order to make way for "Letters from Zedelghem", an epistolary record (addressed to his male lover) of a visit by a musical prodigy called Robert Frobisher to a reclusive old composer in rural Holland. We are in 1931, in the company of a narrator who is languorously English, amoral and aesthetically fastidious. There is some Evelyn Waugh here, a touch of Huysmans and perhaps a debt to John Lanchester's A Debt to Pleasure. At first the reader is given no indication as to how the second narrative might be connected to the first. On first reading, you just trust that a relationship will emerge. Some 20 pages into Frobisher's narrative, there is something to latch on to. He discovers, in the library of the composer's house, "a curious dismembered volume" that is evidently a published version of Ewing's journal. Such links will continue to be "discovered".
The third narrative is entitled "Half-lives, The First Luisa Rey Mystery" and is a condensed thriller, mostly written in the present tense. This comes close to parody in its constant engineering of life-threatening crises for its heroine. Her story in turn becomes a typescript read by the publisher narrator of the next section, "The Ghastly Ordeal of Timothy Cavendish". This disgruntled narration is laced with literary quotes and allusions. The science fiction story that succeeds it, "An Orison of Sonmi-451", is in the form of an interview. Like other versions of an oppressively happy future, it owes a good deal to Brave New World. Finally, "Sloosha's Crossin' an' Ev'rythin' After", as well as being a different version of future fantasy, designedly returns us to primitive story-telling - the "yarnin'" that Mitchell reckons the deepest human inclination.
With these six narratives nested one inside another, there are 10 jumps between genres. Mitchell thus tests and satisfies our appetite for narrative. The novel's success is that, no sooner are you plunged into a new genre, than you find yourself taken up by it, carried along. Yet that is the problem, too. For a genre provides more than conventions for a writer; it also gives a framework for a reader's expectations. Once inside one genre you forget what it is like to be inside another. You may notice with gratitude the "links" to other stories, but the imaginative worlds of those other stories are, of necessity, forgotten once you have left them.
· John Mullan is senior lecturer in English at University College London
· If you would like to respond to any of John Mullan's columns email books@theguardian.com
