Filmmakers Bill Benenson and Gene Rosow had a tough row to hoe when they set out to enlighten mankind about the wonders of soil in their documentary "DIRT! The Movie."

Most people not only take the earth beneath their feet for granted, they tend to treat it like ... dirt.

Narrated by actress Jamie Lee Curtis, the film explains the economic, social, political and environmental impact of soil, and Benenson and Rosow struck just the right balance between earthy humor and sincerity. The point of all their digging: Good soil is becoming an endangered resource worldwide, as agriculture, mining and urban development takes its toll on the land. The results can be catastrophic: drought, floods, mass starvation.

"DIRT! The Movie" will air on KETC-Channel 9 on April 25, but local viewers can get a free sneak preview Thursday as the Community Cinema Series continues at the Missouri History Museum. A panel of local environmentalists will offer their take on the subject afterward.

The film, which was inspired by arborist William Bryant Logan's book "Dirt: The Ecstatic Skin of the Earth," was shot in more than 20 locations around the world, including Argentina, Brazil, France, India, Kenya - and the Rykers Island prison system in New York. Along the way, experts share a wealth of facts and figures about dirt.

Did you know, for example, that 1 teaspoon of dirt contains a billion organisms, all working in balance to support life?

Think about that the next time you dust off your shoes.

Contact Beacon staff writer Mary Delach Leonard.