Despite what you might have heard, we did not collapse into savagery on the 19:26 privatised Virgin Trains service from London Euston. There was not a breakdown of society. We did not revert to barbarism or become like beasts, we did not experience a collapse of social norms, we did not suffer from a brutal upsurge of some timeless human nature in all its frenzy, its envy, and its sanguinary gore. What we achieved on that train was the highest possible expression of modern liberal civilisation. What I saw there, among unseeing eyeballs trailing tails of slime, between its black holes and white walls, was the the truth. The realisation of a perfect idea; at long last, something that works. When the train finally slid into that dry and hungry mouth at Crewe, having experienced minor delays, and we got off to make our connections or to buy a sandwich and a bottle of Diet Coke from the WH Smiths or to wash the blood off our faces in the greasy train-station sinks, we arrived in a world made finally itself.

Start at the beginning. London dribbles in loose splats against the outside of the windows as we speed north. There are parts of the urban chimera that you can only really see out the window of a panting intercity train: the fast-coursing rivers of unused rail and mossy gravel, the heaped industrial shacks groping over each other behind barbed wire, the shockingly naked backsides of terraced houses in grimy brick and spiderweb-cracked plaster with their haphazardly placed windows and their squat forms that bloat like the buried secret of the nice stucco streetside. All these things fade, bursting against the window and trailing off along the sides of the train. London itself fades, staggering into its own twilight. Soon it will be night, and the only thing visible through the train windows will be your own guilty reflection. I am guilty. I am sitting in someone else’s seat. Of course the train is overcrowded; it’s a bank holiday weekend, and thousands are streaming out of London to get the boat from Holyhead – but more than that, this is just the way things are. See how practical questions become moral ones: if you wanted to sit down for your journey, you should have booked a seat instead of getting an open return like the feckless dilettante you are; if you really wanted that seat, you should have been on the platform early instead of wasting five minutes dithering over three types of layered salad at the M&S Simply Food in a drooling microcosm of the delayed-adulthood indecision that is already setting the coordinates for your wasted life and will make sure that your grave is unvisited and unmarked after you die. There are rules; if you can’t play by them then you have nobody else to blame. But trudging through the Gothic infinity of packed carriages, I find an empty seat. Reserved from Milton Keynes Central. And I sit down, knowing that it doesn’t belong to me and I’ll have to give it up, knowing that I am the most worthless creature on this train.

First division. The people left standing, their long line like manacled captives searing through the middle of the carriage, are giving me strange looks. A healthy-looking couple, her hair tied back in a sheer ponytail, his cut short, both of them dangling big hiking rucksacks knotted with strange straps and harnesses, glare. Aleady they want me dead. They know I have no real right to be sitting down and I only got where I am from sheer blind luck. Second division. Out in the vestibule, little eyes peer and scowl behind doors that intermittently hiss open and shut. Third division. In the seat besides me, a balding navy-suited creature reading the Financial Times will sometimes almost-accidentally jab me with his elbow as he lobs peanut M&Ms into his mouth. I hear the flickering neck-snap crackle of candy shells breaking, the damper meatier crunch of masticated peanuts, the slurp and slobber of liquefying chocolate as it gums up the unholy inside of his mouth. He wants me dead too; he knows I don’t belong in that chair, and he hates the fact that to an imaginary observer he might appear to be somehow on the same social plane as an indolent impostor like myself. And me? I hate every one of them, the athletic young couple, the accusing eyes from the vestibule, my peanut-eating neighbour; they’ve seen my shame, and I want it to sprout tendrils and strangle them all.

At Milton Keynes the first skirmishes break out. The platform is packed, and grunts of open hostility greet the people trying to move into the train as others move out. Toes are mangled underfoot, epithets hissed. I give up my seat when the shadow of a tall skinnyfat beardo hovers over me, brandishing his ticket. (It’s hard to tell in the flurry of fake-apologetic winces and grimaces that pass between us as mandated by law – so sorry, no I’m sorry – but for a moment he appears to be wearing my face.) As the train insinuates through rotting late-summer fields I slide into the aisle’s frozen conga. I don’t feel any more solidarity for the seatless as I join their ranks. They certainly don’t seem to feel any for me. At the end of the carriage I see an old man leaning on a stick, stoically mashing his gums. The passengers around him stare into their laps. Not my problem. He should have bought a proper ticket.

Behind me, things are not going so well. A newcomer, short and brutal in a floral print dress, seems to have been allocated a table seat that’s currently being occupied by a family of four – fat gregarious husband, patient hijabi wife, children sucked face-first into their iPads – who also have a valid reservation. The Miltonian still expects them to move, children be damned. She’ll call a conductor. She’ll tell the authorities. When threats don’t seem to work, she leans down, arse bumping against elbows on the opposite row, to grab one of the small children from his seat. The kid screams and flails for his iPad. The husband roars and stands, swings a big broad wobbling punch, catches the aggressor just under her collarbone, and she staggers. The whole line of patient standing-room travellers tilts; I’m knocked forwards into someone’s sweaty shoulderblade. What happens next seems to coruscate in time. In the chaos of that sudden motion a sleek black camping knife tears through the fabric of the big healthy hiker’s rucksack, waiting, mechanically erect. His girlfriend, standing behind him, is knocked forwards, and it jabs deep just under her chin and comes out again, followed by a halting piss-stream of blood. There’s no sound. ‘Whoa,’ he says, noncommittally, as he rights himself; he still doesn’t know what’s just happened. She crumples dead. This carriage is not safe for me. As the first screams rise, and the panic of people crammed immovably in place spreads, I duck and sidle out back to the vestibule. My voyage begins.

This was not, as I discover, the first death. They might have all started like that – accidental – but the killing made too much sense to end that way. In the rubbery intestine between carriages a sprawling clot of people has formed, a pearl around a corpse. The body flails helplessly as the train lurches from side to side, still being kicked and pummelled furiously by an inner ring of maddened passengers; it’s already too disfigured to tell what its age was, or its sex. I don’t ask what crime the victim committed. I already know: they didn’t have the proper reservation. I move on, squeezing past the murderers. Sorry, I say. Sorry, they mutter in reply. The train is a linear Gormenghast, a sucession of reclusive bubble-worlds, each of them with the same decor and the same grisly violence, each brutally different. In the little restaurant car, children run and scream through the burst contents of bags of crisps and other people’s luggage. There’s blood crusting under their nails. They turn dagger-sharp eyes to me, and I move on. In the quiet coach bodies dangle silently from the overhead rail, mouths yawning in wordless screams. I bump my head against one with a barely audible thwock, and a lone impatient tut sounds out from somewhere behind me. I move on. I journey for a very long time, for what feels like years, pushing politely past the killing and the dying, fighting when I have to, fleeing when I can. I’m looking for something. A space where I can catch my breath, just a breath of air that’s not been made humid by sweat and frenzy. No luck. There are, I hear someone whisper, plenty of seats up in first class; you just need to buy a £12 upgrade. Impossible. By this time I’ve seen it myself: the drinks trolleys barricaded against the entrance, the sloping pile of corpses abutting it, every poor mangled idiot still gripping his credit card. And behind them, painted in grime and ichor on the frosted-glass sliding door, the face of the god: bearded, smiling warmly, the faint outlined suggestion of a nude woman clinging behind him on his kiteboard. Not a god who might save us. Richard Branson is a god who has already come to deliver us all.

I soon realise that this isn’t mere anarchy. This is the train responding creatively to its crisis, in the only way a privatised British rail service knows how. All the normal rules of decorum are still in place, the rules that let thousands of people travel amicably across the country while speaking as few words to each other as possible, the rules that give the reservation ticket its magical power and are inscribed in tiny polite jargon on its back – it’s just that the rules that ensure peace are being enforced by increasingly violent means. We are all good and valued customers, and we all have a right to be on this train. It’s just that there’s not enough room for us all. How else can we process our abstract equality? The marketplace of violence will sort everything out. Here, cloistered on a speeding train, we have spontaneously generated the most perfected version of the neoliberal utopia: thousands of subjects, all imprinted with its rational doctrines, working things out. The system is fair, I know it is – because in every carriage I cross, each bristled knotted carpet strewn with blood and viscera, the seated passengers are tapping placidly at their phones, leafing through the g2, idly munching Jelly Babies or nibbling at supermarket sushi, as if nothing were happening at all. Not my problem, their eyes say. They should have bought a proper ticket.

There’s so much I don’t remember.

Not the murder and the bloodshed – I will remember that forever – but more basic facts. Why was I going to Crewe? Why did I leave London and its nurturing stink? I paid, I think, twelve hundred pounds for my ticket. Sometimes I can’t help the vague disquieting feeling that there was someone else with me, that I was idly chatting in my stolen seat to someone important, someone that I knew but can’t now remember, until we reached Milton Keynes and everything started to become the same as it had always been. On this train everyone is only alone. Sometimes, as I edged my way through cacophonous carriages, I’d put a hand against the windowpane and try to look outside, at scenes that felt wrong. Were we moving? Sometimes there seemed to be deserts outside, sloshing dunes in the blue twilight, running like water from vast buried scales, beneath this train gritted still by a million chattering grains of sand. Sometimes I saw the sullen fields of England crisscrossed by tracer fire, paratroopers tumbling strangled from invisible planes, and over the horizon Coventry burning. Sometimes the darkness outside was lit by a tiny pinprick of the noonday sun, burning cold to the faint peripheries of this faraway solar system, where the 19:26 privatised Virgin Trains service from London Euston ploughed through sterile Hadean rock that had glittered lifeless for four and a half billion years, and under contellations unseen by humankind. At one point, I briefly locked myself in the bathroom, shortly before a furious minor tribe ripped out the door. I sat shivering on a toilet seat that pathetically begged with a coprophage’s masochism: ‘Don’t feed me wet wipes or sanitary products – they make me feel very poorly.’ I tried to connect to the onboard WiFi, and instead of a username and password, it asked me for the true name of God.

Despite what you might have heard, I said, we did not collapse into savagery on the 19:26 privatised Virgin Trains service from London Euston. But if I’m honest, I don’t know what you might have heard. As the train finally slid into that dry and hungry mouth at Crewe, having experienced minor delays, I found myself cowering in another vestibule. Most of the others were dead; the screams and gurgles, at least, had faded. And above the bins, behind blood-smeared glass, was a screen showing live CCTV from throughout a clean and orderly privatised train, resplendent with soft comfortable inviting empty seats. The god’s eye view. Onscreen, the only people left standing, or cluttering up the vestibules, were the ones who obstinately refused to sit. There, on one seat, with his hand on his companion’s knee, hunched over an open copy of René Girard’s Violence and the Sacred, scrolling through his phone between its pages, was myself. I remembered the man who had taken my seat at Milton Keynes, the one that looked for a moment exactly like me. He was arriving at his destination. I had no idea where I had ended up. I still don’t know where I am. As the doors pinged and hissed and opened, I stepped out of the 19:26 privatised Virgin Trains service from London Euston, and into the truth.