I hunched my shoulders and glanced along the platform. A little way down, so it didn’t look like we were together, James, Harley, Tamsin and Pete were standing in a group. Harley had his video phone out but he’d just turned it off, again. They were getting impatient.

How long did I have before they decided I’d failed the dare?

“I don’t think you should do this.” Justin hopped up and down behind me.

I ignored him. A bunch of late night commuters sprinted down the steps, glanced at me standing so close to the edge of the tunnel, then barrelled past, slowing only when they saw the display. Three minutes till the next Northern line train. They had time.

Of course, sometimes the displays were wrong.

I looked down at the yellow line again. It stood out, seemingly the only real colour in the filthy tunnel. There were posters on the walls opposite, flanking the station sign: large curved boards advertising Jack Daniels whiskey and “five star hotels at three star prices” in Sharm el-Sheik.

The picture on the Jack Daniels board was black and white anyway. The pyramids on the holiday board must have been bright once. Now the colours were muted and smeared with soot. My eye followed the curve of the tunnel down to the track. Black metal shone in oily lines. My feet trembled.

I leaned so that I could see a little way into the tunnel. It was a black hole, shuddering with the sound of distant trains, the stonework so stained I could barely see the pattern of interlocking bricks. A flash of movement beneath a rail drew my eyes to a small group of mice. There were probably rats in there as well.

In order to come down here I’d travelled on what Tamsin was quick to remind me was the longest escalator on the underground system. I’d felt sick and dizzy all the way, clutching the black rubber hand rail as the moving stair took me down and further down into the earth. I felt as though I’d been swallowed.

Crisp packets moved on the tracks, whipped up inside a sudden cyclone. The mice scurried away and another train appeared in front of me. I rocked back on my heels and Justin steadied me as doors opened a few steps down from where I stood.

A flood of people emerged, jostling, ignoring one another. The commuters who had run past me leaped on. The doors slammed with a high-pitched beep and the train heaved off again.

This time the display said three and a half minutes. I only had to stay in the tunnel for twenty seconds. I’d have three minutes to get there and back before the next train. If I was going, I had to go now.

I rocked forward and Harley raised his phone, but my feet wouldn’t move.

“You’re doing it, aren’t you?” Justin hopped again. “I wish you wouldn’t.”

“I have to,” I hissed.

“If you’re going, you have to go now.”

“I can’t move.” I glanced at Tamsin. She was openly laughing at me. “I can’t let them see me like this.” Tears came into my eyes. “I can’t fail in front of them.”

Justin swore viciously then exhaled. “I’m only doing this because… well, you’ll thank me later.”

Then he shoved me off the platform.

I shrieked as I stumbled forward and my feet met air. Then the back of my head smacked into the rim, my feet thudded on the ground and my shocked ankles collapsed. I shunted forward onto my hands and knees and gasped as my hands closed on the metal tracks.

Above me I heard panicked cries and a woman’s scream.

“Quick, take my hand.”

I looked up. A man leaned over the edge of the platform and his tie fluttered in the breeze that told me a train was moving somewhere. The whites of his eyes showed as he jerked his arm. “Reach for me.”

Justin landed next to me. “You’re here now. Do this fast.”

Tears wet my cheeks as I staggered to my feet. I looked into the tunnel. It was black as the Darkness. The Darkness could be just a few steps away waiting for me to come to It. My pulse raced until it felt like my chest was about to burst open. The only chance I had to save myself was to go into the dark. So I groaned and ran into the tunnel.

Ten steps in, that was the challenge. As I ran Justin ran with me, counting. “One, two, three, four, five, six, seven, eight, nine, ten. Stop, Taylor.”

I screeched to a halt, heart pounding. Pitch black surrounded me like oil in a barrel. I couldn’t breath, I could only whimper in bursts of terror that brought in no air, only soot, and filled my lungs, coating them with darkness, until there was only the dark outside and pitch inside and I couldn’t see a thing.

“Taylor.” Justin was shaking me. “Twenty seconds, that’s all, come on, count with me.”

“I-I…” I stuttered. I couldn’t think, I certainly couldn’t count.

“One, two, three, four. It’s going to be alright. Seven, eight, nine, ten. Halfway there. Twelve, thirteen, fourteen. We’re getting you out of here in a few seconds. Sixteen, seventeen, eighteen, nineteen, twenty. Go, Taylor, GO.” He spun me and shoved me towards the end of the tunnel. I stumbled a few steps and my feet caught on something. I fell and smacked my head on a rail.

My ears rang as I touched the huge egg-shaped lump growing above my eye. My legs were moving though, as if I was still running. They knew what I should be doing.

“Get up!” Justin pulled at my elbow and I let him help me to my feet. Then a whoosh of air yanked my hair into a stream behind me. A McDonalds wrapper tangled on my ankles on its way into the tunnel and I tried to spin.

Suddenly the rush of air reversed. The train was on its way into the station.

Dimly, I heard more screaming. It wasn’t coming from me. My mouth was open, but no sound emerged. The sounds were from above; from the platform.

“Go. You can make it.” I couldn’t see Justin, or the panic in his face, but I could hear it in his voice. I broke into a run.

When I scrambled out of the tunnel entrance the man who had offered me his arm was still there, shouting and cursing at me. I reached for him, but he was too far away.

Behind me the pressure of the oncoming train struck my back, as if it was pushing the air ahead of it, compressing it into a smaller space. “Oh God.”

The words barely formed on my lips and Justin was there. Like a rugby player he slammed into my thighs and hurled me upwards. My gloved hand closed around the stranger’s wrist and he hauled me up, tearing my shirt, hurting my shoulder, but pulling me out of the way of the train. My feet cleared the platform edge just as the engine screeched into the station.

I rolled and the man and I pitched into a clutch of white-faced commuters.

“What the hell were you doing?”

“Stupid cow.”

“Jesus, are you alright?”

Their voices faded to nothing as the train doors hissed open and I spun back to face the tunnel.

Where was Justin?

An arm grabbed mine. “Move it.” I blinked. It was Pete, shoving me through the cluster of angry watchers. “Security will be on their way. Head for the way out.”

“Hey! I don’t think you should be going anywhere.” It was the man who had saved my life. He closed his fingers around my wrist, just above my filthy, soot-stained glove.

“Get off her.” James slammed his fist into the guy’s forearm to break his hold. Then Tamsin and Pete gripped both of my elbows and hustled me along the platform.

“I… I…” I wanted to say thanks. I wanted to find Justin. I’d never seen one of the dead hit by a train. Could you get more dead?

“I can’t believe you did that.” Tamsin was wheezing with laughter. “You should see your face. You should have seen all those people. That might be the best video yet. You reckon, Harls?”

Harley nodded. My feet barely touched the floor as they bundled me past the glowing Way Out sign and up the first staircase.

“Here, take my cap.” Pete jammed a baseball cap over my hair. “The transport police will be looking for you.”