David Mitchell is an original and virtuosic writer about whom I've rhapsodized on this site already. Andy & Lana Wachowski and Tom Tykwer's film adaptation of Cloud Atlas isn't quiiiiiiiite as good as the book, but it's incredibly powerful, moving, intellectually stimulating, creative and visceral, a passion project I wish was more common in big budget filmmaking. It's also incredibly postmodern.
Postmodern? How so?
-It tells six stories instead of one.
-each takes place in a different time period
-each takes place in a different country
-each is in a different genre (sea story, science fiction, farcical comedy, post-apocalyptic fantasy, mystery/suspense)
-each protagonist is from a different demographic
-the stories are woven in intertwining threads. As a viewer you just have to go along with sudden jumps between stories/time periods/genres
-It's conscious of itself as a work of art
-all of the lead actors are cast in all six stories. As a viewer you can't help but notice this as they appear, and it takes you out of the reality of each story, ever so briefly. Sometimes you can't identify them until well into the movie. Sometimes you never do (there were sounds of astonishment from the audience as the credits rolled)
-each story appears in some form as a work of art in another story (the journal entries that comprise the sea story are read in a bound volume by a character in another time period, the adventures of one character in present day are seen recreated as a movie in the science fiction story)
-as mentioned, we jump from story to story in no set pattern. There are similar plot points in each story that happen in succession, edited so that you can't help but notice the mechanics of each story in motion.
-the stories all have the same theme, which is also quite evident in the movie's construction as well.
-Its theme is very postmodern
-one character phrases his philosophy "The weak are meat, and the strong eat." The movie looks at the prevalence of this perspective (which is very modern), and spotlights the impulse to turn it upside-down. Compassion for the downtrodden awakens, and flowers, and attempts to eke out ground amidst the brutality of the strong enslaving, preying upon, slitting the throats of, blowing up, shooting, imprisoning, or otherwise dominating the less powerful.
The movie has post-postmodern elements going for it too.
-the action scenes aren't presented ironically, or as a statement on the horrifying nature of violence - they're genuinely thrilling. And they make violence seem horrible too.
-actors in some stories are cross-cast racially, and sexually. Halle Berry plays a Jewish woman. A white guy plays a Korean guy. An Asian woman plays a Mexican. A black guy plays a New Zealand aboriginal. Hugo Weaving (Agent Smith in the Matrix movies) plays a big, cruel (female) nurse. Any fears of offending the politically correct were eschewed in favour of this decision.
Ultimately, the movie chronicles how, in spite of modernist power that seeks to stay in control through the rule of muscle, fist, bullet, blade and institutional structures, something emerges in the 
human spirit and spreads. Compassion. Equanimity. Empathy. A desire to protect those whom fortune did not bless with superior amounts of muscles, technology and money. And this becomes evident in the actions people take in their interpersonal relations, in their political actions, and in the works of art they create that not only present these themes, but do so in innovative, challenging, accessible ways that make your brain and your soul feel like branches within that had been barren, dry sticks are spontaneously blossoming with bright purple orchids of a beauty and intricacy you'd never considered possible until you suddenly find them abundant, real and divine.
