The Road: A film that every one of us needs to see

As the credits roll and we fall stricken and tear-stained out onto the dark streets of Soho, it seems fitting that I am accompanied by the director of the second bleakest film ever made – Franny Armstrong, creator of the The Age of Stupid. The bleakest film ever made we have just endured together, over two relentless, harrowing hours, and are now so emotionally raw that we know not where we are going, nor do we much care. It doesn't seem to matter. "Oh my God," moans Franny, repeatedly, head in hands.

Remember, this is a woman who has just spent five years creating an on-screen warning about the impending apocalypse. But what we have just experienced takes place on a very different level. The Road is a brilliant, intensely moving piece of film-making, so powerful that it is almost a test of physical, as well as emotional, endurance. By comparison, the specific climate catastrophes that I portray in my book Six Degrees, of killer heatwaves, mega-droughts, spreading deserts and methane-driven runaway warming (the scenarios used in The Age of Stupid, for which I was co-writer), seem almost prosaic by comparison, with their leaden anchors of voluminous scientific referencing. Cormac McCarthy's apocalypse is unstated – he describes just "a long shear of light and then a series of low concussions" – and is all the more realistic for it.

As the Blair Witch Project showed, the unseen horror is always the most unnerving. McCarthy is not expounding any particular end-of-the-world scenario (though it sounds to me most like a nuclear holocaust), but tapping into our collective psyche, into a deep-seated, suppressed fear of what may lie beneath once the fragile veneer of civilisation is torn violently away. The precise nature of the catastrophe that starts the two protagonists' journey in The Road may be unclear, but what matters is that it is all of our worst nightmares added together. It is also a film that everyone needs to see.

The Road as a book is a strange work. It is, in my view, one of the best novels ever written. But it is also one of the most difficult. There is no ironic detachment, no playful cleverness, just page after page of sparse prose, so finely-honed that every word seems hewn out of stone, so perfect and immutable is the sentence that bears it. And its emotional power is indescribable. Perhaps, like A Clockwork Orange, the author would have been well within his rights to withdraw it on these grounds alone: who knows what it could do. Seldom can terror and beauty have been combined so forcefully, and so movingly. For, more than anything else, The Road is a love story, played out between a father and his son whose unbreakable bond is the only thing of value left in an otherwise devastated, lifeless world.

Moreover, anyone familiar with McCarthy's work will know that he cannot be trusted. As demonstrated in the film adaptation of another of his novels, No Country For Old Men, this is a writer who thinks nothing of spending half a film building up an audience's relationship with a character, only to kill them off suddenly in a way so shocking and pointless it is almost offensive – certainly to anyone who believes in natural justice and happy endings. There is no relaxation, no place of safety, no stolid, reliable Gandalf-type father-figure who can never die. The result is edgy and nerve-wracking. In The Road, as either reader or viewer, one tries desperately to emotionally disassociate – to not care what happens to the starving 11-year-old boy and his father as they trudge through the blasted, sunless landscape. But, of course, it is impossible.

"You have my whole heart," says the father to the son. No one but a loveless psychopath could not be moved by that. Knowing what is to happen, it is already an effort not to weep. The reason the story wields such emotional power is because it speaks to what we all share: loving relationships with those closest to us, ties which will one day be broken by death. As any bereaved parent will know, losing a child is quite simply the worst thing in the world. Which parent has not watched anxiously over a sleeping son or daughter, their small, fragile form tucked up in the bedclothes, and not fought to suppress the awful imagining of "what if?" Which child has not looked at a mother and father and imagined themselves as an orphan, alone and bereft in a world full of hostile strangers? McCarthy brings both of these suppressed terrors to the fore and then pushes the knife even deeper; for if the father dies, the boy really will be alone in a world of hostile strangers – robbers and killers who will destroy his innocence with unspeakable violence.

As the man's wife puts it bluntly in a flashback scene before she leaves them alone together: "Sooner or later they will catch us and they will kill us," she says. "They will rape me. They'll rape him. They are going to rape us and kill us and eat us and you won't face it. You'd rather wait for it to happen." The man knows she is right. As the father and son trudge on, they come across meat hooks and blood in the snow, hear deathly howls and gunfire in the night. The film spares no details: a severed head, burned ribs and a puddle of guts are cast under an abandoned car after a band of gun-toting, cannibal thieves have passed through in the night. In a half-destroyed house, the man levers open a cellar trapdoor only to be confronted with a room full of naked, zombie-like, human cattle, kept in chains until their turn for the cull. Under no illusions, the man must now show his son how to blast out his own brains with the last bullet they have left in their pistol, because anything would be better than what the killers have in store if they catch him.

With its relentlessly dystopian premise, McCarthy's world is truly Hobbesian – nasty, brutish and short, suggesting a view of man as in essence little more than base evil once freed from the shackles of sociallly organised moral restraint. Those who can survive are only those who deal death out to others; with all authority gone, only those whose violence is most abandoned and terrifying will triumph. Is this what people are really like deep down without the civilising influence of authority? This question – anxiety, perhaps – is a common theme in art and culture. In Lord of the Flies, after the murder of Piggy, Ralph weeps "for the end of innocence, the darkness of man's heart", whilst in Heart of Darkness itself, perhaps the archetypal examination of the theme, Kurtz sits at the centre of a madman's world of uncivilisation. In both books the severed head is the ultimate symbol of the essential capacity for evil that sits within us all.

And who can doubt that all humans have within us the potential – even the predisposition – to commit acts which are labelled "inhuman" but in fact are anything but? In Rwanda, erstwhile friends and neighbours butchered each other with machetes, as the Radio Milles Collines whispered fiendishly in the background about Tutsi "cockroaches" and the need to shed blood. (Think of the boys' chant in Lord of the Flies: "Kill the beast. Cut his throat. Spill his blood.") During that genocide, even the supposed guardians of good turned to evil: priests and nuns opened up their churches to Tutsi refugees, only to connive in their slaughter once the sun went down. All of us of course like to think of ourselves as moral people; evil is something committed by others. But deep down we all know that this is a self-serving fallacy. What we do depends on our social bonds; without civilisation we would all be uncivilised. The Road asks this same question: can good – personified by the boy, the only one who wants to give when everyone else is taking – survive in a world without rules?

In one scene, the boy and his father meet an old man on the road ahead of them. Against the father's suspicious scepticism, the boy insists on sharing his food with the elderly refugee. As they later sit around the fire – and the boy sleeps, wrapped in tattered blankets – the old man speaks to the father: "When I saw that boy I thought I'd died and he was an angel." Indeed the comparison is apt, because the boy possesses kindness, innocence and warmth in a world devoid of all three; he is as unfamiliar in these devastated surroundings as a real angel would be amongst the crowds in Oxford Circus. The man knows this, and once again McCarthy is exposing every parent's deepest fear – for what father as not looked at his son's sleeping form and wondered whether he is too good for this world? The man is a survivor, but the tenderness of his gestures betrays his vulnerability. He understands his role as parent and protector in the starkest possible terms. "My job is to take care of you. I will kill anyone who touches you," he tells his son evenly. The practicalities of parenting may be about education, food and shelter, but McCarthy has defined it in its rawest, animal form – parenting as an ape or a tiger would understand the role – to destroy anyone who threatens your young, even at the risk of your own life. When innocent children are murdered, whether by a Myra Hindley or a Fred West, it is sin in the purest form; the definition of unforgivable evil. Yet in The Road, it is would-be child-killers who rule the daytime and the open spaces. In such a world, even survival makes little rational sense. In this post-apocalyptic landscape, there is nothing to live for: no sun, no flowers, no food. So why survive? For man and boy, the answer is simple: for each other, and each other only.

Whilst it is built on an end-of-the-world premise, The Road is very different from conventional apocalypse movies. While the spectacular celluloid catastrophe of 2012 contrived to entertain and titillate more than to scare, this has more in common with Independence Day and The Day After Tomorrow (all three of course being Roland Emmerich creations) than with deeper examinations of the human psyche like Mel Gibson's gruesome and deeply unsettling Apocalypto. It is perhaps relevant that the conventional narrative of the 'end times' – a pervasive theme in all Judeao-Christian thought and scripture which reaches its best exposition perhaps in the biblical Revelations – seems to have been discarded by modern Western culture: in 2012 it is the Mayan calendar (exotic and mysterious) which contains the unfolding prophecy of doom. Today the Christian meaning of Armageddon is of interest to only a few fringe US evangelists involved in a cultish movement that they call 'the rapture'. In comparison, real-world fears of the world's end – building on the threat of nuclear apocalypse during the Cold War, now replaced by worries of ecological overshoot and consequent social collapse – seem to be increasing all the time. Perhaps these film treatments of the theme, unrealistic as they may be, are simply plugging into these nagging 'end-times' worries.

And of course these current scenarios of apocalypse are scary precisely because they are not mythical but are based on a rational survey of the state of the planet. The Cold War was all too real, particularly after the near-catastrophe of the Cuban Missile Crisis. Today, global warming has come to occupy a similar niche. In The Age of Stupid, the opening panoramas survey a similarly wrecked planet to the one in The Road: we see the Sydney Opera House backed by an advancing wall of flames; a baked-brown Matterhorn devoid of snow; the garish neon lights of Las Vegas half-buried, forgotten, in the sands; a vulture tearing at a human corpse outside the Taj Mahal. The scenes were not invented outright but extrapolated from the scenarios predicted by climate-change computer models if carbon emissions continue to rise. The precise figures are arguable, but what seems beyond doubt is that the old order is breaking down; temperatures at the end of this century will probably be higher than they have been for tens of millions of years.

There is little to reassure us in a world where the future is going to be so unlike the past – indeed, we are now entering a new geological era, in which the major chemical cycles of carbon, water and nitrogen have all been altered immeasurably by human activity. How far will we have to push these planetary stresses for cracks to appear in our modern civilisation, and for the evil within us all to tear once more across the land?

The warning The Road is not of a specific outcome arising from a specific course of action which we need to change. Unlike The Age of Stupid, it is not about what might happen if we don't "seal the deal" in Copenhagen. The Road is about the human condition, and how humans might behave to each other if the worst does happen, in whatever way. If we ever do push the planet so far that the majority of the human race is left without food or water in uninhabitable areas, what will it feel like to be one of the starving millions? Initially we might all come together in adversity, in a kind of global blitz spirit. McCarthy admits this possibility: at first, others had "come to help" the survivors. But "within a year there were fires on the ridges and deranged chanting. The screams of the murdered. By day, the dead impaled on spikes along the road." We won't stay united for long.

How can anyone prepare for this kind of outcome? Over the years, I have received many emails from people asking where they might need to set up home if runaway global warming begins. New Zealand, perhaps? Norway? I'm sure all the questioners share the same survivalist fantasy, the one where they take their family into the hills and survive on a small farmstead, stockpiling rice and baked beans and keeping a loaded rifle by the well-guarded front door. The Road exposes even this limited comfort as being futile: sooner or later the ammunition will run out, the pounding on the door will begin to splinter away the hinges, and the ravening, faceless horde will pour in. If the worst happens the truth is that there is nowhere to hide, and the road itself will offer no comforts. Of that we can be certain.

"Are we still the good guys?" asks the boy plaintively after his father has had to resort to violence to protect him. If they are, it is not just because they refuse to sink into cannibalism and thievery, but because of the love they share for each other – father and son are "each the other's world entire", as McCarthy writes in the novel. This, and only this, gives their lives meaning. It is nothing short of the difference between life and death itself, and this is surely the essential message of The Road. For without love there is nothing – just smoke and ash and gunshots echoing in the lonely, freezing darkness. Love is the light; the delicate, stuttering candle that they – and we all – must hold against the all- consuming darkness of death.

Mark Lynas is a British environmentalist whose books include High Tide: The Truth About Our Climate Crisis (2004, Picador) and Six Degrees: Our Future On A Hotter Planet (2007, Fourth Estate)

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