The movie is simplicity itself. There is no narrator. They just shove the camera in the face of whatever runner they are interviewing. Prior the race they talk to last year's winner, a skinny small Mexican-American guy who works at Les Scwhab and is popping out from under a car during the interview. He says anybody who would do that again would have to be crazy (in a beautiful Speedy Gonzales accent w/ perfect upward inflection). You get to meet a number of other entrants the same way -- in their natural setting.
Only 40 entrants are selected based on their applications w/ resume. Eventually the race starts. All is fine through the first 120 degree marathon. At 30 miles trouble crops up. The stout marine Corps major is the first to be seen on the side of the road wretching from a curled/bent over position using all his enormous back muscles to evict a small slimy stream of bile. He's got heat exhaustion, and it's a thing of beauty.
One entrant, a 65 year old dipsatch driver for Lloyds of London has run 250 marathons and many, many ultras. His only support crew is his wife, also a soft-spoken witty Brit. At mile 70 he pukes, washes his mouth out, wipes off his face, pops his false teeth back in and starts running again. His wife eventually tapes a can of Irish Stout to the back of the car to lure him to the finish.
Oh, the enormous pussy blisters. Unbelieveable. The completely dazed look of the finishers. You gotta see it.