Blood on the rocks

Towards the close of this harrowing tale of survival against all the odds and most of the elements, the climber Joe Simpson is dragging himself down through the jumble of rocks at the end of a glacier.

He's dehydrated and delirious; his leg isn't broken but mashed, the tibia having smashed through his knee joint. Then it happens - the final, insane indignity - he begins to recall the ditty Brown Girl in the Ring. Around and around his tortured head the inane lyrics are pursued by the tinkly instrumentation. In voice-over Simpson laconically remarks: "I thought to myself, bloody hell - I'm going to die to Boney M!"

Mountaineering tends to be ill served by film. In the past few years there has been David Breashear's IMAX documentary about Everest, the 1996 filming of which - either serendipitously or tragically, depending on which way you look at it - coincided with 15 deaths, the most fatalities seen on the mountain in a single season.

Then there is the cable-staple Cliffhanger, in which Sylvester Stallone failed to suspend our disbelief in his climbing quite as much as his acting. It's strange because, given the drama of the sport and the grandeur of its setting, you'd have thought mountaineering would appeal more to filmmakers; certainly it has been well served by writers, and many of them have been climbers themselves.

Arguably the most dramatic of recent mountaineering books is Joe Simpson's Touching the Void, which Kevin Macdonald, the Oscar-winning director of One Day in September, has now made into a dramatised documentary.

Simpson was one of the tyro Alpine-style climbers to emerge in the 1980s. Eschewing the militarism of earlier high-altitude expeditions, with their legions of bearers and well-supplied camps, the likes of Simpson aimed to get to the top of perilous peaks toting their own gear and with no back-up. It was a jaunt of this kind which, in 1985, took Simpson and his companion Simon Yates to a particularly savage little eminence in the Andes, Siula Grande.

The west face of this 21,000ft dorsal fin of rock, snow and ice presented just the sort of challenge the pair were looking for: it was unclimbed and had defeated several other attempts. But while the ascent proved a gruelling testament to their skills, it was on the way down that Simpson discovered his true gift in life - falling. A plunge of a few metres on the summit ridge telescoped his leg, but at that altitude Simpson knew he was finished. What followed was first an astonishing rescue as Yates lowered him down the sheer face of the mountain, and then a terrifying choice. Simpson plunged over an ice cliff; Yates, unable to pull him up and about to be pulled into the abyss himself, remembered that he had a penknife in his rucksack.

Touching the Void thus has all the requirements of Greek tragedy, from the hubris of the young climbers to the revenge of the mountain gods.

That Simpson survived against such incredible odds is confirmation - if any were needed - that climbers are not as other men. Frankly, their endurance and physical heroism makes Jonny Wilkinson look like the proverbial big girl's blouse.

Macdonald's film juxtaposes dramatised reconstructions of the climb and interviews with the three protagonists: Simpson, Yates and another young Englishman, Richard Hawking, whom they left at their