The Book...
Written by David Mitchell – not the one from Peep Show – Cloud Atlas was published in 2004 to the excited whisper of literary critics going quietly gaga. It made the shortlist for that year's Booker Prize, and the fact that it ultimately missed out to Alan Hollinghurst's The Line Of Beauty hasn't stopped it maturing into a much-loved work of contemporary fiction. People who read it back then rhapsodised about the way it tombola'ed different genres into six mesmerising, interlocking narratives, swept up in its ambition and scope. (They also said things like: "There's no way they'll ever make this into a movie" but we'll gloss over that.)

The Film...
Directed by Andy and Lana Wachowski and Tom Tykwer, a talent troika about whom we're legally obliged to use the word 'visionary', it's a collaboration of filmmakers as well as actors. "It's never been attempted before, I don't think", says cast member Ben Whishaw, "three people sharing the directing responsibility of a film." It could equally be argued that, with six storylines to shoot, three directors is three too few. Still with Tykwer and the Wachowskis boasting a CV with films as diverse as The Matrix, Bound, Speed Racer, Run Lola Run and Perfume: The Story Of A Murderer, there was no shortage of creative firepower when the film's Berlin shoot kicked off in September 2011.

The Script...
The book's unique six-story structure – think of a Matryoshka doll with story strands fitting neatly into one another – posed a unique challenge to the three writer/directors. In short: how to ensure a single, coherent through-line without the film (a) confusing the heck out of audiences or (b) lasting 14 days. That process took a year. "We decided that if David Mitchell didn't like it, we'd kill the project," says Andy Wachowski. "Fortunately he loved it."

The Production...
"Hard to explain, hard to finance" is a Hollywood truism – which is why we won't see David Foster Wallace's Infinite Jest on the big screen anytime soon. "Even though we had this incredible cast, no-one was interested," remembers Andy Wachowski. "The experts said it was too complicated", laughs his sister Lana, "and three directors? That's never going to work." With the exception of Warner Bros., who'll distribute the film in the US, the team were left without big studio backing and turned to German banks, film funds and tax breaks to raise a budget that producer Stefan Arndt puts at "definitely lower" than $100m.

As Andy Wachowski stresses, it is very much an indie movie, albeit with more multi-genre quantum-leaping than your average mumblecore. Each story had its own production unit, with Tykwer focusing on the period elements and the Wachowskis unsurprisingly turning their hands to the sci-fi storylines.

The Plot...
Make that 'plots' plural. The six stories begin in the 19th century with American actuary Adam Ewing (Jim Sturgess) sailing home from the Chatham Islands, recording his voyage in a half-finished diary that resurfaces in the hands of penniless musician Robert Frobisher (Ben Whishaw) in 1930s Belgium. We then find Frobisher's penpal and lover Rufus Sixsmith (James D'Arcy) as the scientist in Reagan's California who lays bare a nuclear conspiracy to investigative journo Luisa Rey (Halle Berry).

Still with us? Good because now it gets really complex. Rey's story – Half-Lives: The First Luisa Rey Mystery – eventually lands in the lap of vanity publisher Timothy Cavendish (Jim Broadbent) in Noughties London, and his character's fate ties in with a dystopian clone in a near(ish) future called Somni-451 (Doona Bae). Then that leads on to a post-apocalyptic Hawaii where tribesman Zachry (Tom Hanks) and Meronym (Berry again) try to evade cannibals, including a terrifying Hugh Grant. Yes, we used the words 'terrifying' and 'Hugh Grant' in the same sentence.