In October, with cameras rolling, Engle will attempt to run the equivalent of nearly two 26.2-mile marathons a day for 80 straight days over fierce terrain — the Sahara Desert in northern Africa.
He and two others — Kevin Lin, of Taiwan, and Ray Zahab, of Canada — will seek to become the first to run 4,000 miles across the Sahara.
Charlie Engle got the idea for the Saharan run three years ago while winning a race across the Gobi Desert in northern China and southern Mongolia.
He convinced Academy Award-winning actor Matt Damon's film company, LivePlanet, to do a documentary about it. Damon, who'll narrate, won't focus only on the runners, which Engle said "would be like watching grass grow."
They'll run 10 to 12 hours for 50 miles daily, then visit sites and mingle with natives.
"Running the Sahara" will be about human endurance, as well as the beauty and diversity of the Sahara, its 2.5 million mostly nomadic people and their daily struggle to find water.
He knows the film will bring change. A recent Canadian newspaper story brought hefty donations.
Matt Damon will officially announce the documentary Sept. 10 at the Toronto Film Festival, where it will premiere the same time next year.
Shooting and running begin Oct. 25 in Senegal and, if all goes well, end Jan. 25 at the Red Sea in Egypt. In Mali, the expedition will visit Tombouctou , or "Timbuktu," a symbol for remoteness.