Then, above the low moan of the infected, she became aware of a distant, thumping sound. It was far away but getting quickly louder. As well as the thumping she could hear what sounded like the whirr of an engine.
She pushed on. Just a few more minutes and they'd be clear.
The sound got louder. Closer. The infected heard it too. Their moaning intensified.
She paused and glanced over at Anita.
The girl was staring at the sky to their left.
Lisa followed her gaze.
The distinctive dark outline of a helicopter was travelling towards them, fast, from the south, following the path of the motorway.
For an instant, Lisa couldn't decide whether to run or freeze.
She froze.
When it reached them, it swooped down low, hovering directly above their heads. The wind from its rotating blades pinned them to the ground. They could hardly lift their heads. The noise was deafening. Combined with the, now frenzied, cries of the infected, it created a wall of sound that obliterated everything else.
Then, sheets of paper began to flutter from the sky, swirling in the wind, blowing across the motorway, the roundabout and into the streets beyond.
Lisa managed to turn her head and look up. The side door of the helicopter was open and a man in army fatigues was gesturing at them furiously. Lisa just stared at him. Her head was empty. She felt distant … detached … like she was watching a movie scene that she wasn't part of.
"Lisa!" Anita's voice cut through the fog. "Get up! Run!"
Anita was standing. Her body was bent and braced against the blasting currents of air. Her long braids flew around her head like a medusa. She was pointing towards the slip-road.
A group of infected were coming over the top. They looked angry, hungry and dangerous.
The helicopter arced and soared, up and away over the motorway again, continuing north.
Anita was running. Lisa scrambled to her feet and followed her.
Another group of infected were coming up the other side of the motorway on their right.
They reached the road. Infected were appearing from all directions … both sides, in front and behind. The noise seemed to have served as a rallying cry ... drawing them out … summoning them.
"They're everywhere!" Anita cried out. "There's nowhere to go!"
"Just keep going. We can avoid them, outrun them!" Lisa yelled.
Fired by adrenaline, the women blasted through the group in front, weaving between them, twisting and dodging to avoid their grasping, clawing hands.
But, more and more appeared. The road ahead was a mass of seething rotting flesh, bearing down on them.
"There's too many!" Anita sounded desperate. "We're not going to make it!"
Lisa frantically glanced around her.
A large white shape on a driveway to their left caught her eye and she instinctively spun and ran towards it. It was a huge camper van, the type the Americans call an RV. One door was ajar. She was at the door and inside before she had time to think about it.
Anita was right behind her, but so was a large, beer-bellied, greasy-haired, male infected, in baggy shorts and a too-tight polo shirt. He got to the door a fraction of a second before her.
Again, without thinking, a primal survival instinct kicked in as Lisa braced herself in the door frame and, screaming, kicked out with both feet. She hit it square in the centre of the chest, and it toppled backwards. Anita scrambled over it, kicking and stamping on its flailing limbs. She tumbled into the van and Lisa slammed and locked the door behind her.
Gasping and shaking, they cowered by the door. Outside, a multitude of infected clawed and scratched at the van. The noise was deafening. The whole vehicle swayed and rocked.
Lisa closed her eyes. She covered her ears to try and block out the sound. Flashbacks of the train toilet flooded in. With it came the fear. The same paralysing terror and fuzzy, light-headed feeling. She felt herself losing control. She could hear herself breathing fast and loud, and her pulse was pounding inside her head, but she couldn't control it. She put her fingers in her ears and began to hum. Not a tune exactly, just a flow of monotonous random notes. Anything to drown out the noise. She was only vaguely aware of Anita by her side, who was also lost in her own ocean of terror.
It was a long time until the noise outside subsided. The deluge of scratching and clawing gradually gave way to just an occasional bumping and scraping. Somehow, the van had remained secure and upright. It was big and heavy. A smaller vehicle would almost certainly have succumbed. Lisa didn't want to think about what could have happened.
Warily, they moved into the interior of the van on stiff and cramped limbs. Most of the curtains inside were drawn already and, keeping out of view, they closed those that were not in a series of tiny movements, including the one that separated the cab from the rest of the space.
The van was packed with bags of clothes, boxes of food, camping equipment and packs of drinking water. Whoever had loaded it had been preparing to get away. Lisa thought about how the door had been open and wondered who they were and what had happened to them. There were no signs of a struggle.
Anita was more concerned about finding the keys. Having checked the ignition, she was now rummaging around in drawers and compartments.
"I don't think they're here." She sat down heavily. "Shame. It could've been perfect. Our own little mobile fortress. Sweet."
"Well, we're not going anywhere tonight. We might be able to have a proper look in the morning. It's getting dark now."
"Yeah, totally. Sounds like there's only
