With our time on Earth coming to an end, a team of explorers undertakes the most important mission in human history, traveling beyond this galaxy to discover whether mankind has a future among the stars. (Paramount Pictures)

This post discusses the plot of the movie “Interstellar.”

Early in Christopher Nolan’s space opera, we see a number of older people on screen, recalling what it was like to live through a natural disaster. “My dad was a farmer back then, like everybody else. Of course, he didn’t start out that way,” reminisces a woman. “When we set the table, we always set the bowls upside down,” recalls a man.

One of the older women, Murphy Cooper, is played by the actress Ellen Burstyn. But the rest are not actors. They are interview subjects from Ken Burns and Dayton Duncan’s 2012 documentary “The Dust Bowl,” and they are speaking about their experiences in that real environmental catastrophe, rather than a fictional cataclysm.

“Interstellar” is the first film to which Burns’s Florentine Films has licensed content from a Burns project. And Nolan’s use of Burns’s  material provides a fascinating window into what the director is trying to say about human actions and environmental responsibility with “Interstellar.”

Duncan told me that Nolan approached him and Burns more than a year ago to pitch them on the idea of using “The Dust Bowl” material in a new context. “He called me up and he said how much he had enjoyed ‘The Dust Bowl,’ how much it had really moved him, and he was really incorporating it into a film he and his brother were making,” Burns explained. “Here he was, hearing in [the survivors] the universality of their circumstance, and how contemporary that was. What he was doing, you could hear the ambition in his voice.”

They agreed, on two conditions: that Paramount approach the Dust Bowl survivors to get their permission to use their interviews directly, and that Duncan and Burns could read the script. A producer flew down with the script, waited until Duncan was done, and flew the copy back to Canada, and Burns and Duncan signed off on the project.

In “Interstellar,” humanity is endangered by a blight that is gradually eliminating the number of crops that are viable on Earth. The world economy and national governments have shrunk dramatically. Drones race through Midwestern skies, abandoned by the intelligence programs that set them aloft, and crash into fields where they are scavenged by entrepreneurial farmers like Cooper (Matthew McConaughey), a former pilot who still dreams of flying. Violent dust storms straight out of documentary footage of Dust Bowl storms rise like mountains in the skies, and the particles fill children’s lungs, killing them. If Nolan does not make explicit that the disaster is man-made, his use of testimony from actual Dust Bowl survivors means that he does not need to. “I think it made this potential thing of earth’s future cataclysm, environmental cataclysm on a world-wide scale very palpable and real, and the use of our stuff enhanced that,” Duncan told me. “This really happened. It’s just a question of could it happen on a global scale, or in such a way that our existence on the planet would be imperiled?”

For Burns, it is actually more powerful to let audiences come to their own queasy conclusions about the Dust Bowl, and the kinds of problems that have humans looking sky-ward in “Interstellar.” “Everyone’s heard of the Dust Bowl but no one ever really understood its extent, or more importantly that it was a man-made environmental disaster,” he argued. “That’s the key. When you fully begin to accept your own culpability in this, as the people in the Dust Bowl do, they begin to reach out for help and solutions, which in the Dust Bowl, come from the New Deal and Franklin Roosevelt.”

“Interstellar” never explains the source of the blight and the dust storms that plague Earth’s remaining residents. But its characters do learn that while they initially thought a race of superior beings was intervening to save humanity, they alone are responsible for their own species’ survival. And by including the voices of Dust Bowl survivors, Nolan has done his own part to preserve their testimony.

“To me it was just gratifying to know, on their behalf, that what they have to say about this moment in time is now going to keep on living and reaching people,” Duncan said. “I really hope that those folks are going to get to go sit in a screening and so they and their children and their children’s children could go see them in a Hollywood production. They’re often in small places, small towns or farms. And it’s good to see that what they had to say was deemed powerful enough, their testimony had such power that it couldn’t be exceeded by fictionalizing.”