There are many things I am uncertain of, sitting here on this platform, but of one thing I'm sure: Somebody does not belong here. 

I steal another glance at the blonde-haired teen sat cross-legged on the floor in front of me, a little to the left, as he strums a tune on his guitar. His head is down, bobbing lightly, as he watches his own fingers produce a melody that none of the rest of us particularly enjoy. And yet, for his sake, we do not voice it. He is not playing to pass the time; he's not even playing to impress us. I suspect he plays because the silence of this unearthly platform makes him uncomfortable, and he knows why he's here.

Beside me, curled up with her legs drawn into her chest, is a young woman. She rests her chin on her knees, keeping herself closed off from everybody else. Her hijab is untidy. Strands of her hair fall in front of her doe-like eyes as though she'd fixed her appearance in a hurry this morning. Her expression is blank, and I want to ask her how long she has been staring at that crack in the floor tiles for. She knows why she is here, but not the reason.

Alone, at the far end of the platform, sits a hunched figure in a black coat that comes down to his knees, turned away from the rest of us. He perches on the only object on the platform – a kind of concrete block – with his knees spread apart and his elbows rested upon them. I've been staring at him for a while now and he hasn't moved an inch. I'm not even sure he's breathing. He's been here the longest and now, as time continues to dilate, he grows exhausted. This man knows why he's here, and he's waiting for the train like an old dog awaits its master's return.

The remaining two are a couple covered in blood. The man – dark-haired, in his early thirties and dressed in what was once a perfectly ironed suit – cradles his girlfriend. His fingers dig into the bruised skin of her upper arms, leaving pale circles whenever he readjusts his grip. The woman sobs under her breath; her grief is evident in the pink flush of her eyes and the way her hands writhe restlessly with the hem of her dress. She doesn't want to cry in front of her partner, but she knows why she's here and it's consumed her. I sense her boyfriend also knows why he's locked down here on this platform, but he is only fooling himself if he thinks he can undo his fate before the train arrives.

Lastly, I gaze up at the announcement board for the Helatide and heave a vocal sigh. What did I expect would change? There are no departure times, no stops, no destinations written in those orange LED letters, only scrambled numbers with no meaning that punctuate each heading. The announcement board has been broken since I got here, though I no longer know how much time has elapsed since I descended the stairs to the platform. Behind me is the track that the train, wherever it is, runs on: a single blue beam of light pulsating like the screen on a heart-rate monitor. I've never before seen a train in an underground station run on a track like that before, and, of course, I have to wonder how it works. What does it look like? And where does it go?

Over to my left, the teenage boy begins to hum to his tune. He's probably never heard himself sing before, or none of his friends and family have ever had the kindness to tell him he's insufferably tone deaf. But the silence is worse. His strumming at least tunes out the girlfriend's sniffs and sobs. Still, none of us chide him. The bedraggled soul beside me bores her gaze further into the cracked floor tile, the couple a little farther away turn a deaf ear to the world, and the mysterious man at the far end of the platform hunches still as a gargoyle.

How much longer will this dreaded wait continue? How many more hours will it be until we hear anything but our own thoughts and the twang of guitar strings? I shouldn't complain; I only have myself to blame for being here. The whole adventure had been my stupid idea. I, too, know the reason I've wound up on this platform, waiting for the Helatide to arrive. I sense every one of us knows our situation, why we are here, even if we don't understand it, and yet something isn't right. One of us doesn't belong here. Why can't I get it out of my mind?

The man in the black coat gets to his feet, and all heads in the room turn in his direction except for the teenager's. The man stands for a moment, listens, and his fists curl.

"Cut it out," he growls. I note his American accent.

The boy with the guitar finally lifts his gaze, stops mid-strum and his mouth falls open a little. I make eye-contact with him and nod towards his guitar.

"About time," the man says.

"Who, me?" asks the boy. He sounds too cheerful. Too annoying. "Something up with my playing?"

"If you knew what kind of a place this is, you wouldn't be doing anything at all. Just sit still, shut up, and wait for the train like the rest of us."

The boy puts his guitar down on the tiles with deliberation. "I know what kind of place this is," he replies. I have to commend his sheer boldness to answer back to the man in the black coat. I know I wouldn'tve. "I've known for a whole two years I'd wind up here."

I lift my chin. "Two years?"

He shrugs. "Cancer," he says, and his gaze falls on the track behind me. His deep brown eyes flash with each pulse of blue light. Finally the man sits again, resuming his brooding. "You?" the teen says to me.

"I guess I drowned, after all," I answer. "I totally thought I could make it ..."

"What happened?"

The memory still brings me shame. I hope my friends don't blame themselves for leaving me behind. I hope my parents still find some pride in me even though I'd always been a reckless idiot. "I was ... exploring. You know, some caves off the coasts of Sri Lanka. Thought it would be fun to get high there; make a cool story of it when I finally returned home. The tide came in, and my friends and I got trapped, and I ... guess I didn't get out in time."

"I'm sorry," he says.

I sigh again. "Shit happens. At least those I left behind can say nature bested me, and not anything or anyone –"

"Careful what you say next." The young woman beside me wraps her arms around her legs.

"What happened to you?" the teen with the guitar asks.

"I don't want to talk about it."

"And where else can you talk about it?" grunts the man in the black coat. "We're all here for the same thing. Nothin' anybody does or says can change what'll happen when Helatide gets its damn ass here."

I touch the girl's arm. "You don't have to tell anybody, if you'd rather not."

"I never want to relive that moment," she whimpers to the floor. "Never. Never. Never. There was nothing I could do. Nothing I could ... I couldn't save myself from them ..."

"Shh. It's okay."

"Hey," the teen says, turning to the distressed couple at the back. I cringe inside. How can he be so cheerful at a time like this? Is he blind? "What happened to you two?"

The blood-covered man catches his girlfriend's eye before answering. "RTA," he mumbles in response, and hangs his head again.

"RTA?"

"Road traffic accident," the man in black interjects.

"I'm sorry," he says to them with a sad smile. "I'm sorry for you all, actually. You've all had a pretty rough time. As for me I knew I'd end up here and, sure, it was scary from the word go, but I've made the last two years count. I've said my goodbyes, done everything I wanted to achieve, seen all the places I wanted to see. No regrets. I'm sorry you all couldn't do the same."

I speak up. "Is that why you're so happy about being here?"

"I wouldn't say I'm happy, but I accepted boarding the Helatide when they told me I was incurable."

"So did I," says the man the far end of the platform. "Don't mean I'm happy to be here."

"What happened to you?"

The man finally turns towards us, throwing out the lengths of his black coat as he does so. His face is hard and harsh, his small brown eyes piercing in the gloom. He's bald on top, though sports a bushy grey beard and sideburns, and I spy the glint of a gold ring through his septum. "You wanna know what happened to me?" he half-chuckles. "Some guts you got, kid. Some guts. Don't you know who I am?"

"Nope," the teen says. "You're American. I'm from New Zealand. Should I know?"

The man snorts. "Prob'ly a good job you don't. Mauricio Talamantes. Name ring any bells with ya, kid?"

I take a sharp breath. "The Rosemont shootings ..."

The corner of his mouth lifts. "Damn right. Kid asks me why I'm here. You gonna tell him, or do I gotta spell it out?"

"You were on death row," I whisper.

"Yeah. Been on death row almost a decade. Still feel sorry for me, Aussie boy?" The boy with the guitar shakes his head. "Right answer, and so you shouldn't, but don't be so hasty to judge. Last thing I saw's that machine pump me with some lethal injection shit. Sure, I got some regrets outta it, too: regrets I got in too deep, regrets I've gotten myself caught. Regrets my little boy ain't never gonna know his papa and end up just as bad as I am. But" – he leans in and rests his elbows on his knees again – "what can I do about it now? Time slows down in here, kid, an' when you're waitin' for that goddamn drug to kill you, days turn into weeks down here. You, Indiana Jones." He thrusts his chin at me. "You got regrets?"

I have to think about it. Nothing immediately comes to me. I was a privileged only child, did well in school, lived the party-life at university, failed it, and travelled the world ever since. What was I missing? "I disappointed my parents, I guess," I tell him. "Drank too much, slept around, smoked stuff I shouldn't have smoked. After that I disappeared without a word and left them behind. Never made them proud; never got a chance to say I'm sorry for turning out an idiot."

He addresses the woman in the hijab. "What about you, girlie? Pretty little thing like you got a name?"

She doesn't look up at him. Still, the crack in the tile requires her immediate focus. "I–I don't know. I can't think," she mutters. "I just ... I wish I'd been able to see. I mean ... see the monster he was."

"What about you two lovebirds?" Mauricio asks the couple. I sense his question is not welcome, as the pair let it hang in the air. "C'mon. We're all boarding any time now. Ain't none of us gonna see each other again, and ain't none of us gonna get a chance to confess like this. Any regrets? I sure as hell ain't askin' again."

"I ..." the bloodied man begins, "I was driving too fast. We were having an argument. I wasn't looking where I was going and ... I've ruined everything for us. Our future, our –"

The woman in his arms speaks for the first time. "I don't hate you, sweetie. I didn't mean what I said."

"Well," says Mauricio, "ain't that cute."

"There's still something on my mind," I say.

"More regrets?" asks the teen.

"No. No." I run my fingers through my hair. How do I put this without sounding nuts? "We all know why we're boarding the Helatide. Illness, murder, lethal injection, three accidental deaths. But one of us doesn't belong here. One of us shouldn't be on the train, and I don't know why I know it."

The blonde-haired boy looks down at his hands. "I feel it too, as though something is wrong. Does anybody else feel it?"

The woman beside me nods at the floor, and Mauricio sighs with a heavy heart. The man in the bloodied shirt gives me a sad smile and nods, too. The only one on the platform that doesn't respond is his girlfriend.

"Is it you?" Mauricio asks her. His voice is not tender, though I can tell he tried. "You don't belong here, missy, do you?"

She sniffs and her eyes brim with tears again. "No," she says. "I shouldn't be here. I need to be at home. I need to be back where we came from for –"

"I'm so sorry," her boyfriend whispers, burying his face in her hair. "I'm so, so sorry. Don't say it. Don't say it."

"You think you should be the one who escapes the one-way train?" Mauricio spits. "Like hell. You might be here by accident, but as Indiana Jones over there says: shit happens. Accept it. You'rehere. And you're stuck down here until the trains rolls in. Might as well make the most of what time we've got left in limbo."

"Not me," the bloodied woman sobs. Finally, after all this time, her partner lets loose his feelings, and his face contorts into grief. He clutches her hair and sobs.

And then I understand.

"Not me," she repeats.

I watch in horror as she rests a shaking hand on the bump in her abdomen.