How do you make a movie version of "On the Road," author Jack Kerouac's near stream-of-consciousness ode to bumming back and forth across Eisenhower-era 1950s America and Mexico in hitched rides, purloined cars and hobo boxcars in a blur of jazz joints, poetry and longing? The book is all about first-hand, lived experience expressed in a euphoric rush at the sheer joy of it all. As a director, how can you faithfully re-create that without losing that crucial sense of immediacy and intimacy, without making it feel like the guy who's dating a woman who looks exactly like his ex-wife?

Many have wrestled with the problem in the decades since "On the Road" was published in 1957, and it finally falls to Brazilian director Walter Salles to give it a shot. It's easy to see why he got the call from producer Francis Ford Coppola, who's held the screen rights since the '70s: Salles did an excellent job with a similar road-trip-as-self-discovery book, successfully adapting Che Guevara's "The Motorcycle Diaries" in 2004. Salles believes that for a road movie to feel real, you have to actually travel, and he spent several years prior to filming tracing Kerouac's roots and travels.

What Salles finally settled on is an "On the Road" that is not so much the novel per se, but an impressionistic homage to its creation. The story of young Sal Paradise (based on Kerouac, and played by Sam Riley ["Control"]) and his infatuation/admiration for the wired, restless Dean Moriarty (Neal Cassady, played by Garrett Hedlund) and their crisscrossing of America remains intact, but Salles expands on it, drawing not only from "the scroll" — Kerouac's original manuscript for the novel typed out in one mad Benzedrine-fueled rush — but from the memoirs and letters of friends and lovers whose lives informed the characters. Dean, in particular, comes across half the idolized American drifter of the novel, but also as the irresponsible, fickle husband and friend.