Among the accomplishments one might hope to amass over a lifetime, running the entire length of the Sahara may not come up on many personal to-do lists.
Yet that was the grueling goal for ultra-distance runners Charlie Engle, Ray Zahab and Kevin Lin. Their exhaustive exploits are explored in the documentary Running the Sahara, airing on Showtime (premiering Sunday, 9 ET/PT).
The three completed what's believed to be the first run across the world's largest desert.