For a playwright or screenwriter, this is a normal day at the office, but the first read-through of the “Cloud Atlas” script will stay with me forever. With three or four actors unable to attend, the film’s directors — Tom Tykwer and Lana and Andy Wachowski, who also wrote the screenplay — divvied up the spare roles. It seemed rude not to volunteer. I hadn’t been in a group-reading situation since my high-school English class, but instead of my 17-year-old classmates slogging through “A Passage to India,” here were Tom Hanks, Halle Berry, Hugh Grant and Jim Broadbent delivering lines that sounded uncannily familiar. The whole experience felt rather like finding Gandhi playing Connect 4 with your plumber in the cupboard under the stairs — it wasn’t so much the individual elements of the scene that were surreal but their juxtaposition.
Yet it soon sinks in that you’ve morphed from being the Creator to the guy who happened to write the original novel. How this makes you feel depends, I guess, on how you feel about the adaptation itself. I’ve never experienced much anxiety in this quarter. I met the three directors in 2008, and their plan to foreground the novel’s “transmigrating souls” motif by having actors perform multiple roles (each role being a sort of way station on that soul’s karmic journey) struck me as ingenious. Some changes to plot and character were inevitable, so that the book’s six worlds could be coaxed into a film-shaped container: the love interest between the (now) middle-aged Zachry and Meronym on postapocalyptic Hawaii, for example, or Cavendish’s epilogue, which appears in the film but not the book. Moreover, the novel’s Russian-doll structure has become more of a mosaic — you can’t ask a viewer to begin a film for the sixth time after a hundred minutes.
Wherever the “Cloud Atlas” screenplay differed from “Cloud Atlas” the novel, it did so for sound reasons that left me more impressed than piqued. (At the read-through, I sat next to Lana Wachowski, and when a line earned a particularly strong response, I’d whisper, “Was that one of yours or one of mine?” The tally was about 50-50, I think.) Anyway, film adaptations of novels are prone to failure not because they are too faithless but too faithful: why spend all that effort producing an audiobook with pictures?
Production! My week on set in Berlin, in December 2011, gave me access to a world I’d heard of but never visited. Look — there’s a clone-recycling unit where there wasn’t one 60 minutes ago; look out, fiberglass mountain outcrop coming through; what, are all high-tech sliding doors in S.F. movies made of painted plywood?
I filled a Moleskine with notes from informal interviews with a range of professionals I never encounter in my solitary-ish novelist’s life: language coaches, script editors, costume and set designers, C.G.I. animators, entertainment lawyers, caterers, extras, a futuristic vehicle designer, stuntmen. I acquired a heightened respect for actors too: There was nothing computer-generated about the water drenching Halle Berry up to her neck; and David Gyasi, who plays an English-speaking 19th-century Moriori islander, riffed from a pitch-perfect Maori accent to Caribbean and then to African with the ease of a man changing hats. Thanks to my cameo appearance, I also learned how many hours are spent in the trailer for every minute on screen. Little wonder some actors become voracious readers.
Tagging along after the Wachowskis and Tykwer for a few days encouraged me to compare my own addiction of writing novels to the relatively vast operation of filmmaking. Perhaps where text slides toward ambiguity, film inclines to specificity. A novel contains as many versions of itself as it has readers, whereas a film’s final cut vaporizes every other way it might have been made. Funny thing is, not even the author is immune to this colonization by the moving image. When I try to recall how I imagined my vanity-publisher character, Timothy Cavendish, before the movie, all I see now is Jim Broadbent’s face smiling back, devilishly. Which, as it happens, is fine by me.
David Mitchell is the author of five novels, including “Cloud Atlas,” adapted into a movie by Lana and Andy Wachowski and Tom Tykwer, out this fall.

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