By James Rocchi
Special to MSN Movies

Published in 2004, author David Mitchell's "Cloud Atlas" featured intertwined characters living in six separate timelines, with important thematic and symbolic connections weaving between them. Reviewers and readers were rapturous and impressed by a dizzying set of structural games and puzzles that both demanded and rewarded close reading. When Lana and Andy Wachowski of the "Matrix" trilogy and "Speed Racer" announced that they were bringing the book to the screen alongside "Run Lola Run" director Tom Tykwer, the question was almost less how they could pull it off than if they could. According to those lucky enough to have seen the film at the Toronto International Film Festival or Austin's Fantastic Fest, they succeeded. Or came closer, in their way, than any other directors or director might have. In a recent essay for the New York Times, Mitchell noted that, "Wherever the 'Cloud Atlas' screenplay differed from the novel, it did so for sound reasons that left me more impressed than piqued."

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The challenge of adapting an "unfilmable" book has played a siren-like song for many directors actors and producers, with the promise of glory in victory balanced against the greater possibility of foundering and then sinking. We thought we'd share the past efforts of great directors eager for a challenge, and lesser-known talents hungry for success, to bring "unfilmable" books to the big screen.