Into the Wild, Sean Penn’s movie adaptation of the best-selling book by Jon Krakauer, is both a celebration of youthful idealism and a devastating cautionary tale. Its careful balancing of these divergent viewpoints is one of the strengths of Penn’s screenplay, resulting in a fascinating journey that will provoke discussion especially among twenty-something audience members just starting to find their purpose in life like the film’s ill-fated real-life protagonist, Christopher McCandless.

For older viewers, Into the Wild will prompt nostalgia for that time when the great themes of literature connected with the possibilities of one’s daily existence, when wanderlust seemed an awfully attractive alternative to forging a career path. The film respects, even reveres that impulse, but it’s clear-eyed enough to understand when the quest for pure freedom and rejection of societal norms themselves become impediments to personal fulfillment.

McCandless was the son of a NASA aerospace engineer and a recent graduate of Emory University when he simply disappeared from his family’s life in the summer of 1990. He changed his name to “Alexander Supertramp,” gave his entire $24,000 college fund to OXFAM America, and eventually abandoned his car and burned all his ready cash on an unstructured journey across North America. That trek took him from the wheat fields of South Dakota to the Colorado River to the missions of San Diego, before he set off for his ultimate destination: exploring the wilderness of Alaska completely on his own. There, he was fortunate enough to find an abandoned bus to use as a home base, but his luck would eventually run out; unprepared for the flooding of his path back to civilization, he would starve to death, his body found by hunters 16 weeks after he entered the woods.

McCandless was foolhardy and arrogant, and the movie doesn’t shy from that fact. But it also immerses us in his singular adventure, and the beauty of the actual locations captured by cinematographer Eric Gautier (The Motorcycle Diaries) conveys the appeal of his bold and reckless dare. For all his quoting of Tolstoy, London and Thoreau, McCandless’ rebellion is mostly motivated by his hatred of his parents, especially a distant dad who kept it a secret that he was still married to his first wife when he fathered Chris and his devoted younger sister, Carine. Ironically, Chris keeps encountering parental surrogates on his journey: a middle-aged hippie couple (Catherine Keener and Brian Dierker, the film’s water stunt coordinator) who lost their own child; a rowdy farmer (Vince Vaughn) who traffics in illegal cable boxes; and an elderly recluse (the marvelous Hal Holbrook) who still mourns the long-ago death of his wife. One can’t help thinking if Chris had been as open to the stories of his own parents, this trip to find himself might not have seemed so urgent.

In the extremely physically demanding role of McCandless, Emile Hirsch (The Lords of Dogtown, Alpha Dog) holds the screen throughout, combining Chris’ callow hubris with an innate likeability, especially in his scenes with Keener and Holbrook. Close your eyes and he sounds like a younger Leonardo DiCaprio, and his performance here bears comparison with that one-time teen Oscar nominee. Also a standout is Jena Malone as Chris’ compassionate, heartbroken sister Carine, who deftly handles the sometimes florid narration Penn wrote with poet Sharon Olds.

Penn’s sensitive handling of all his actors is no surprise, but he also shows a keen eye for the American communities and vast landscapes McCandless traversed. A story of youthful narcissism that never neglects the poignant humanity at its core, Into the Wild speaks to the yearnings and frailties in all of us.