The Paramount Classics film is based on Jon Krakauer's nonfiction book "Into the Wild," about a man who wandered off unprepared near the national park and died.
According to Paramount spokeswoman Aurora Belchic, the current shoot in the park is focused on Christopher McCandless' last days as he starved to death. The set is largely the Alaska landscape, punctuated by the abandoned bus where moose hunters found McCandless' body in 1992.
Belchic said filmmakers will make one more trip to film in Alaska. The final, four-day shoot will take place at an undisclosed site in late August. At this point, there are no plans to hold casting calls for Alaska extras. Paramount would not release any more details.
Though the book empathized with McCandless, portraying him as a free-spirited adventurer, many Alaskans were scornful of his deliberate hike into unfamiliar territory with little food and no compass or map.
Only time will tell how Penn chooses to portray McCandless. The success and credibility Penn has earned as an actor in films such as "Dead Man Walking" and "Mystic River" haven't historically followed him behind the camera.
McCandless is being played by Emile Hirsch, star of "Lords of Dogtown" and "The Dangerous Lives of Altar Boys."
The 21-year-old actor is the least-known member of a star-laden cast that includes Oscar winners William Hurt ("A History of Violence") and Marcia Gay Harden ("Mystic River") as McCandless' parents.
During the protagonist's hitchhike to Alaska, he runs into a fellow tramper named Jan Burres played by Catherine Keener ("Capote"). Film industry publications tie Vince Vaughn ("Wedding Crashers") to one of two roles in the film: a South Dakota farmer or Alaskan Jim Gallien, who picked up McCandless and tried to help him.
The Alaska scenery is in the hands of French cinematographer Eric Gautier, who was behind the gritty, quasi-documentary style of "The Motorcycle Diaries."
According to newspaper and wire reports, "Into the Wild" filming took place earlier this month in Astoria, Ore., and Carthage, S.D. There were shoots in Nevada in June and Fairbanks in April, as well.
On July 7, the Sioux Falls (S.D.) Argus Leader printed an interview with Carthage grain elevator owner Russell Dillon, who advised Penn on South Dakota authenticity.
"Sean Penn was very particular," Dillon told the Argus Leader. "He wants it as real as possible."
The film's release date has not been set.
Daily News reporter Sarah Henning can be reached at shenning@adn.com or 257-4450.
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