PARK CITY, Utah - When he was just 11 years old and living in Princeton, Robert Stone borrowed his parents' Super 8 camera and made his first film, about the pollution he saw around him. He made it in honor of the country's first Earth Day, which was held that year.
Thirty-nine years later, Mr. Stone, now a well-known documentary filmmaker, has made "Earth Days," a film about the start of the environmental movement in this country. It was recently given the honor of being chosen as the closing film at the Sundance Film Festival here in Utah.
"There's a direct line from the movie I made as a child in Princeton to the film that I've just done," said Mr. Stone, 50, who now lives in Rhinebeck, N.Y., with his wife and two sons. "Much of what I have to say about the world hasn't changed all that much. I just express myself better now."
His first film was a children's crusade; he and his friends saw students at Princeton University protesting the war, and they were inspired to protest something, too, he said. "Pollution is something that really hits home for kids," he said. "We got it right away."
For his first film, Mr. Stone and his friends interviewed people on the street in Princeton about pollution, and scaled a barbed wire fence around the university's main heating plant. They climbed on top of the building to film friends "dying" from pollution.
After attending Princeton High School, Mr. Stone studied history in college. But he soon became serious about making movies. For his senior thesis, he wrote about the nuclear testing program on Bikini Island in the Pacific Ocean, and decided to make a documentary on the subject. It took him seven years, but when he was finished, "Radio Bikini" was nominated for an Academy Award for best feature documentary in 1987.
Since "Radio Bikini," Mr. Stone has made nine feature documentaries. His work has been screened at dozens of film festivals, and televised around the world, and his first retrospective was held recently in Canada.
In "Earth Days," Mr. Stone said he wanted to tell the story of how America awakened to the environmental crisis. The first Earth Day, on April 22, 1970, is considered by many to be the start of the environmental movement in the United States, and it galvanized ordinary people to get involved in saving the environment.
He tells the story through the lives of nine people who made a major contribution to the environmental movement, including the entomologist Paul R. Ehrlich, whose teenage years were spent in Maplewood and who is known for his work on population growth, and Rusty Schweickart, a Neptune native and former astronaut who became California's energy commissioner.
Mr. Stone is known for his skill in using archival footage, which he weaves throughout "Earth Days," said Geoffrey Gilmore, the director of the Sundance Film Festival.
"There's a real clarity and story to this work," Mr. Gilmore said. "Robert is exceptional; he finds things that no one else could discover. This film has a gorgeous quality that sparkles off the screen."
Mr. Stone, whose father, Lawrence Stone, was a noted history professor at Princeton University for many years, said he wanted to use his film to consider the environment in historical terms.
"So many of the films and books I've seen and read about the environment have been about looking forward; where we'll be in five or 10 years from now," Mr. Stone said. "But it occurred to me that by looking back to where we've come from, what we've learned could be very informative in where we are going and how we move forward."
Ken Brecher, the executive director of the Sundance Institute, also had praise for "Earth Days."
"I love the film because it's very inspiring, and it says something about our individual responsibilities when it comes to the environment," Mr. Brecher said. "This is one of the big issues of our times, and at the moment, film is the best way to communicate."
"Earth Days" will be released in theaters on Earth Day, April 22. After a yearlong theatrical run, it will be shown on "American Experience" on PBS.
"In many ways, this film is my world view, writ large," Mr. Stone said. "And it's not a very different world view from the one I had as an 11-year-old kid, when I saw pollution all around me."