The first we knew of it was in double English. Mr. Chapman waxed poetic about the works of Edgar Allan Poe when he glanced out of the window and froze. We all jumped up in our seats to look.
We might have known earlier but our room was at the back of the school, away from the car park, so all we could see was murky brown rising above the trees between the playground and the shopping centre on the other side. We'd seen smog before, but this was nothing like it, swelling quickly, a swath of choking haze beneath what had previously been clear blue.
"The windows!" Mr. Chapman called above the eruption of shocked babble, and we nearest the windows sprung to closing them and latching them tight. He ordered us to stay in our seats, then murmured, "I'll just..." as he spun toward the door, as lost as the rest of us. He didn't get far, nearly bowling the headmaster over as the man appeared in the doorway.
"Yes, yes, we know," the headmaster barked. "It's the cars, all of them, pumping that muck out. Gardner's men are trying to turn them off, and we've got calls in to the police, but in the meantime, we've turned off the air and you should close your -" He glanced up. "Ah, you've already got that. Well done." He turned to the class. "Now you're all to stay in your classrooms. Keep calm and we'll sort it." His nervous, forced smile, meant to be reassuring, convinced us of the grave danger more than a stern look would have done.
"You heard the headmaster," Mr. Chapman called, clapping smartly. "Now, let's get on with the lesson." He turned back to the blackboard.
He made a good go at carrying on, but we were having none of it. Three of the kids pulled out their mobiles and tried to call home. The devices weren't common those days and we had mocked them for having them, pretending that we weren't deathly jealous, but at that moment, we wished we were them. It didn't help, of course: they couldn't get through. The rest of us cowered together, staring out of the windows and whispering, and Mr. Chapman gave up, sitting down with us at the windows.
It wasn't long until we smelled the smoke, a touch of acrid poison filling our noses. As the minutes wore on, the haze outside thickened and the chatter inside lightened, false gaiety against looming suffocation. We spilled out into the corridor when the air in our tiny room became humid and stale, joining with our schoolmates to joke and gossip, because silence was far more terrifying. We ignored the intermittent fits of coughing.
Then, a scream of terror, and we rushed to the windows. A wall of flame consumed the sky, the heavens themselves burning and roiling. I clutched at the girl next to me and we cried as we huddled against the cataclysm, but when the hellfire never came, we looked up. The air was clear and the sky was blue. Only the faintest hint of smoke remained, and when we opened the windows, that cleared soon enough. We stared at each other in wonder, not daring to believe that we were still alive. There was nothing else for it. Mr. Chapman dismissed us and we trudged home in silence, wondering at the sudden catastrophes that plague us and our inexplicable miraculous salvations.