He didn’t take his eyes from me. “After you,” he finally said, “it was all I had.”

James grinned horribly. “And don’t forget the videos we’ve got of you, mate.”

“Shit.” I punched the table. “Shit, shit, shit.”

“Tay?” Justin grabbed my elbows. “What’re you waiting for? You have to Mark him.”

“You helped kill someone, Pete.” I spun back to him. “You and Harley, James and Tamsin.”

“Keep your voice down, you stupid slut.” James’ brows were so low I couldn’t see the expression in his eyes. “V’s all about what we’ve got on each other. You promised you wouldn’t tell, but if you forget and open your mouth, remember we could get you locked up for that little stunt on the underground.”

I spoke only to Pete. “Justin was your friend.”

Pete nodded, his face miserable. “It didn’t seem so bad doing little things. It was surreal, like I wasn’t involved at all.” He shook his head. “If I could tell him how sorry I am…” He looked at me. “I didn’t want you involved in this, Tay. I tried to tell you to stay out.”

“I-I know. I couldn’t.” I showed him my hand. “I’m supposed to touch you with this.”

“Do it.” Justin pushed me and I lurched forward, just missing Pete’s elbow.

“Stop it,” I hissed. “Just stop it.” I was finally crying. “It’s Pete, I’m not going to Mark Pete.”

I ran out of the restaurant. Behind me I heard James shout. “After her.”

Chairs clattered and a waitress yelled as they sprinted after me. Where did they think I was going?

I crashed through the double doors, out into the street and a bubble of silence.

It’s here.

I spun to find the Darkness rising in front of me like a pillar. I stared into its black heart and my shoulders drooped. I’d chosen this when I’d let Pete go clean.

Around me the street was silent. At the edge of my vision people walked on the other side of the road, eyes turned from me. They didn’t see the Darkness, but they instinctively chose to avoid its presence.

My lip trembled but I raised my hand, showing the Mark almost defiantly.

The world seemed to draw breath and I knew the pillar was about to crash over me.

“Don’t just stand there.” Justin barrelled into me, grabbed my arm before I could hit the ground and pulled me into a stumbling run.

“Justin, it’s over,” I gasped.

“No.” He shoved me in front of him. I saw him look back then he pushed me harder. “You aren’t going with that thing.”

Behind me there was a muffled thud. I dug my heels in and turned. The bar door had slammed into the wall. Harley, James and Tamsin were lined up on the pavement. Pete was hanging back.

“There she is.” James pointed. “Get her.”

I had time only to blink before the Darkness struck. Tamsin didn’t even have time to scream. I met Pete’s horror-filled eyes as his friends vanished, swallowed as if they had never been.

“It’ll come for you now.” Justin shoved me again. “Run.”

Sure enough the Darkness, like a beast unsated, seemed to be seeking a scent. I hesitated one more second and it spread out on the pavement like it had turned to liquid, then started to flow towards me.

I caught my breath, looked briefly at Justin and ran.

I’d never seen anyone outrace the Darkness before, but it was worth a try.

“It’s gaining.” Terror bleached Justin’s voice and even though he was right at my side, his words sounded like a distant cry.

Fireworks flashed in my vision. I dug my fist into my aching side as we sprinted through a silent world and ahead, people parted like a biblical sea, unknowingly moving for the Darkness.

As we turned the corner a Routemaster pulled away from the bus stop.

Justin propelled me forward. “Get on.” He literally threw me toward the back of the bus. With my last ounce of strength I grabbed the bar; then moved out of Justin’s way. He leaped on after me and gripped my hand as we turned to see if the bus was going to be able to outpace the spreading tide of black.

Shadowy fingers reached for the wheels and crept up the sides of the vehicle.

I retreated into the glowing interior.

The bus was full but the noise inside was muffled. A couple of kids pressed their fists against their ears as if they had just popped.

“It’s here,” I whispered.

“I know.” Justin pushed me ahead of him to the stairs and I ran up two at a time. The top floor was empty, but we’d trapped ourselves; there was nowhere else to go.

For a couple of seconds, at the top of the bus, sound rushed back into the world and my ears pounded with the roar of the engine, horns from outside, a lone siren and a bus of chatting Londoners.

I allowed myself to inhale, then the void came crashing back down and everything was muffled once more. I wheeled. The steps behind me were black; as I watched, the last one vanished under a dark blanket.

I looked at Justin, focusing on his chocolate eyes. “I’m sorry I couldn’t help you.”

He squeezed my hand and I had to strain to hear his reply. “I wasn’t sure about this moving on thing anyway.” He fingers crushed mine. “We need more time.”

I trained my eyes back on the Darkness, clinging onto a childish feeling that the thing in the dark couldn’t get you if you watched it.

The bus shuddered to a halt and I staggered. The lights that glared into the window were red. The Darkness advanced more quickly.

“I wish you hadn’t had to hear that back there, about your friends.”

“They weren’t my friends.”

The seeping shadows seemed to be taunting us, surrounding us on all sides, but not yet closing in.

Suddenly the bus lurched and sped up. I glanced out of the window. We were finally on the Westway, able to move much faster.

I held my breath and the Darkness slid back as if it were a blanket being yanked off a bed.

“We’re beating it.” Justin punched the air.

We stood beneath the fluorescent lights in the centre of the aisle and when sound returned to the world I threw my head back, closed my eyes, bathed in the racket and tried to forget that it was impossible to outrun the Dark.

At the end of my road we leaped from the bus straight into a sprint and hurled ourselves directly towards my house.

“Nearly there.” Justin pulled ahead and half dragged me behind him.

We ran through the pools of orange light cast by the streetlamps. Light-dark, light-dark. Each time we left a circle of brightness I caught my breath, fear clutching at my throat as my foot landed outside the glow and pitched me into the twilight of the spaces between.

I didn’t know why I was running for home. The Darkness would find me there as easily as anywhere else. I only knew it was the only place I’d ever felt safe, and my Dad was there. Part of me needed to hide behind him, but really I wanted to say goodbye.

We pounded up the steps and I fumbled with my key as Justin watched the road behind us. “Tay.” His voice contained a warning, but I knew what I’d see if I turned around: the shadows linking the streetlamps growing murky and starting to flow together.

“Quick.” I grabbed his hand and dragged him through the door. Then I ran for the study. “Dad!” For the first time I burst inside without pausing at the threshold.

I staggered to a halt. It was bright in the study, electric lights blaring yellow as sunshine. Dad was bent over a microscope. As I entered he straightened and a smile cracked his face. “Taylor, what good timing.”

“No more samples.” Automatically I put my hand behind my back.

“Not that. I’ve got good news.” He rolled back from the desk. “Look at this.” He gestured towards the slide beneath the scope and I glanced at Justin then released his hand. I put my face to the eyepiece then blinked. “What am I looking at?”