Self-indulgent is the word for Sean Penn’s new film, referring not only to its style—which swoons and luxuriates while telling the story through various forms of narration (spoken and written) and devices that can seem very affected—but also to its protagonist. “Into the Wild” is an adaptation of Jon Krakauer’s book about Christopher McCandless, a Thoreau-obsessed Emory graduate who abandoned his upper-middle-class family and law school prospects for hobo life as a self-styled “supertramp.” His peregrinations took him to what he foresaw as a kind of personal paradise—the uninhabited wilderness of Alaska—where he spent some months in a sort of ecstasy of solitude, only to find himself stranded in the spring thaw, and died torturously after poisoning himself with some berries he mistook for edible.

On the purely pictorial level, the picture is pretty spectacular. The locations—which range from the wide wheat fields of the Dakotas to spectacular southwestern mountains and white water rapids and, of course, the isolated Alaskan wilds—are gorgeous as caught by Eric Gautier’s magnificent widescreen cinematography. Many of the images can’t have been easy to shoot, but one never feels the difficulty, just the overwhelming result.

And most of the characters Chris spends time with on his journey are engaging people, nicely played. Vince Vaughn does his voluble rogue shtick to considerable effect in the South Dakota sequence, and Brian Dierker and Catherine Keener are both engaging and strangely touching as an aging hippie couple who adopt the boy but learn from him, too. Best of all, Hal Holbrook does some of his best work since “All the President’s Men” as an elderly widower who befriends McCandless just before his fateful Alaskan trip. The final scene between the two is heartbreaking. Slightly less impressive are Kristin Stewart as a free-spirited sixteen-year old who comes on to Chris at a commune and Thure Lindhardt and Signe Egholm Olsen as an exuberant Scandinavian couple he meets on the river.

Unfortunately, the family McCandless leaves behind—to whom the movie periodically returns—are far less incisively drawn. Chris’ resentment of his parents—high-handed father Walt (William Hurt) and doting but nervy mom Billie (Marcia Gay Harden)—for their animosity toward one another and lack of attention toward him and his sister Carine (Jena Malone) is presented as the cause behind his decision to wipe the slate clean and go native. But though the one-dimensional portrait that emerges of them can be dramatically justified by the fact that it’s based entirely on their son’s perspective, it’s still one-dimensional, and even performers as gifted as Hurt and Harden can’t invest the characters with depth. Nor does Malone do much with the Carine, despite (or perhaps because) she’s saddled with lots of overwritten narration that—along with plenty of the same spoken by Hirsch—provides most of the background that’s supposed to explain the young man’s unhappiness. Humbert Humbert famously wrote that you can always count on a murderer for a fancy prose style; the narration here suggests that the same is true of privileged but neglected children.

The larger issue, though, is that while the people McCandless comes upon during his travels are an engaging lot, he himself—despite all that narration, presented rather preciously by Penn not only in spoken words but written passages ostentatiously emblazoned on the screen in various fonts and typefaces—and Hirsch’s deeply engaged performance (which must have been physically very demanding, especially given the weight loss involved), remains an obstinately opaque figure, and a more than slightly unsympathetic one. His self-centeredness and almost casual dismissal of the people who care about him—not just his parents but the people he meets along the way—are meant, one supposes, as evidence of the mysterious inner need that drives him, but are nonetheless hardly admirable traits, and though toward the close he adds to his journals the epiphany that happiness must be shared, it seems an observation far too little and too late. Throughout the film one desperately wants to feel an emotional connection with Chris McCandless, but despite Penn’s and Hirsch’s yeoman efforts—including a long sequence of his killing and skinning a moose in Alaska, which many viewers will probably find repulsive rather than revealing—it never comes. As a result it seems a visually stunning modern-day epic in which the protagonist, unfortunately, remains a blur—certainly more so than the central figures in two recent documentaries about naïve souls who similarly failed to recognize the dangers posed by the natural world, “Grizzly Man” and “Deep Water.”

“Into the Wild” represents a decline from Penn’s previous directorial effort, “The Pledge,” which was less episodic and substantially more moving. (Of course it was based on a source, Friedrich Durrenmatt’s fine novel, which gave it a backbone that Krakauer’s book, for all its virtues, lacked.) One has to admire the commitment behind the film, and the artistry with which it’s been executed; but you may leave wondering whether this story can bear the weight that Penn has chosen to put on it.