The annals of literature and film are filled with stories of young people (usually men) who take to the roads in search of something, most often themselves. It's a particularly American idea that has turned into a particularly American rite of passage, sending folks with dogeared copies of On The Road in their back pockets out to thumb a ride to parts unknown.

This fact is not lost on director Sean Penn, and it is something that fascinates him and in some ways still calls out to him. At least that's the impression that he gives with his careful and passionate retelling of the story of Christopher McCandless. The young man, fresh out of Emory University, left a life of relative privilege behind and took off on a journey across America, one that would ultimately spell his demise.

I feel comfortable telling you that as this story has already been recounted in Jon Krakauer's book of the same name, which uses interviews with Christopher's friends, family and the people he met on his journey to paint a fascinating portrait of someone who felt completely removed from what we consider to be normal, everyday society, and therefore felt it important to remove himself from it.

But whereas Krakauer has the luxury of a few hundred pages to really explore the psychological underpinnings of someone who would make such a decision, Penn can only really scratch the surface with this material, but he does it in a way that reaches deep into the core of a yearning that can be found in most people - an urge to simply get away. Penn adds to this by putting the McCandless character into contact with other wanderers and outcasts, trading stories and wisdom and often practical advice.

As much as it can be seen in those terms, the film is also a not so cleverly shaded environmentalist tract, showing one person's interaction with a sometimes dangerous, sometimes forgiving, but always beautiful natural world. If the film, in some small way, encourages people to interact with or even protect places such as the ones seen throughout, Sean Penn has done his job.

But, because he is quite obviously a talented director and storyteller, Penn does so much more, challenging our preconceptions, daring us to watch this young man take steps some of us can only dream of taking ourselves, and asking us whether we could/would do the same thing.