FILM / A perfect recipe for disaster: Adam Mars-Jones on Alive, based on a true story of cannibalism and heroism

For once, the logo that precedes all Paramount Pictures gives fair warning: for a little over two hours, the viewer of Alive will be looking mainly at snow-capped mountains not all that different from the stylised one in the graphic before the credits. If the experience of watching is an ordeal, then that is not exactly a complaint. Arguably, if it wasn't an ordeal it could only be an insult to those who survived, and those who died, when a plane crashed into a mountain in the Andes in 1972, and the rescue effort was called off, as it turned out, in error.

The story of the Andes plane crash raises question about the morality of survival - would you do anything to stay alive? Anything? - and those are questions that the film would dearly like to address. After all, if the Fairchild F-227 twin-engined turboprop that plunged into the mountain had been carrying a cargo of corned beef, say, as well as people, then it's unlikely that a film would have been made of what happened afterwards, even if the survivors had endured twice as much as the historical ones did. But before the film can hope to tackle issues of cannibalism and taboo it must necessarily raise questions about film genre, about the structures of untruth we call entertainment. It may be human to overcome extremity, but it may also be perverse to choose to watch it.

The advertising material for the film shows the problems with eerie clarity. The chosen slogan - They Overcame the Impossible By Doing the Unthinkable - could hardly be more uneasily divided between promises of heroism and horror. But the chosen image, though also in two parts, emphasises only triumph. Three men climb doggedly towards us, away from the wreckage of the plane. The dead bodies necessary to the climbers' survivors aren't visible. The message here seems to be: they did it] They climbed the mountain] (Undertone) Oh, and there was a plane crash. (Barely audible) Oh, and they did what they had to.

Meanwhile the upper part of the image is occupied by the grinning faces of the two survivors who walked to Chile. These radiant faces tower over the mountains, and only the emphasis on the teeth in those grins summons up, if only on the level of sick humour, return of the repressed, the price paid for survival.

The film, directed by Frank Marshall from a script by John Patrick Shanley (who perpetrated Moonstruck) makes a much better job of smoothing over the contradictions than the poster, but they're all still there. It is hard to see how you could stage an air crash without including some element of the spectacular, but later incidents have a jarring overtone of almost Indiana Jones-style big budget derring-do or elation - a cliff-hanging scene over a crevasse, for instance, or a ride on improvised toboggans. Why are we shown the pictorial beauty of an avalanche, when for the characters it is experienced only as a hammer-blow slamming into their fragile shelter, killing eight of them?

The music, meanwhile, by James Newton Howard, alternately sombre, wistful, awestruck and triumphant, is almost entirely composed of false notes. It's as if his score was based on the poster rather than the script. Perhaps somebody should have told him that little detail of eating human flesh. Or perhaps the aestheticising, emotionally editorialising nature of film music is necessarily doomed in a film that has to keep returning to the body and its limits.

Not surprisingly, Marshall has taken great care with the scenes of actual cutting and eating flesh. At first, when Roberto (Josh Hamilton) approaches one of the bodies in the snow with a jagged piece of glass, it looks as if we're being let off with a long shot. Then we do see a close-up, but the body is sufficiently changed by the freezing cold that its humanity is distanced and obscured. It is at a moment like this that a human body is most evidently both meat and a person, and later on we can see flesh laid out to thaw like bacon from a freezer, or mortal chops being loaded into a backpack, with relative equanimity.

The characters' experiences were suffused with Catholic imagery, and the film must follow suit. For the most part it does so tactfully. Many viewers will draw the line at Aaron Neville's singing 'Ave Maria' in his convulsive vibrato over the closing credits, and it's true that the analogy between eating human flesh and the Eucharist would be more haunting if somebody didn't make it explicitly. We can see for ourselves that after Roberto has broken the ice, as it were, the others (those who have decided to eat) reluctantly assemble as a group to approach the bodies, like a congregation after the celebrant has partaken. But even in the first days of the ordeal, when it seems that rescue must be imminent, the sharing out of rations - wine meted out into a beaker, chocolate broken scrupulously into squares - already has something suggestively sacramental about it.

Two of the survivors have broken legs. One of them develops gangrene over the many weeks that passed without rescue, while the other enters a state that no one actually says is one of beatitude, but no one says it's a benign narcosis of the brain either. We're allowed to keep an open mind about whether prayer averts avalanches, but we are shown that an ominous rumbling dies away when the single agnostic finally joins in the telling of the rosary. The camera sometimes profits from the interludes of prayer to back off a little from the group and its agonies, or to yearn faintly up at the sky, but it must return to secular priorities.

Nevertheleses, like Lorenzo's Oil a couple of months ago, Alive accidentally destroys the genre of which it tries to be a part. The sufferings of children in Lorenzo's Oil were too real to be outweighed by any medical breakthrough or revelation of family love, and in Alive the genre mechanisms that are meant to make us identify with the strongest survivors fail to function. None of us knows what we would do in a real crisis, but watching Alive we are likely to feel that it is more understandable, more truly human, to lie down and die than to out-stare death, to attempt the endless walk to the green valleys of Chile. The adventure-movie genre invites us to share vicariously in heroic will, but here we are likely to experience a despair by proxy that makes the eventual triumph of some of those who crashed on the glacier hard to share. It may be that after two hours in the cold we are simply too numb to feel the warmth of returning life.

(Photograph omitted)