“How did he kill the dog?” said Tam.

“What?” Rand was driving slowly and scanning the streets. Every time he saw some bloodstained hobo he would stab the brake and spin down a different street. His forehead was knotted into a frown that didn’t suit him at all. He was normally so Zen.

“Another Wreck got mauled by that same dog,” said Tam. “Caleb managed to kill it. I saw a dog carcass like that before but I guess I’d assumed it took more than one Wreck to beat it. This time, I dunno…”

“When we find him, let’s ask him,” Rand said dismissively.

“Rand,” said Tam with something like a pout. She got his attention. “Shouldn’t we be trying to answer these questions? Isn’t that why we’re doing this?” Rand took a few deep breaths before responding. Then he apologised and said that he was stressed out trying to find Caleb when they couldn’t go more than one block in a straight line.

“Don’t avoid them, go through them,” said Tam. “We have a duty to annihilate as many of them as possible.”

Rand shrugged. “I’ve been distracted,” he said. “Honestly, I’m obsessed with the idea of the Cause. What it is, what it means. I think I want to go there more than I want to find Caleb and watch him. I think the answers are there.”

“That’ll be Zombie Central Station by the time we get there,” Tam said. “You might survive it, but I won’t.”

“The possibility of my survival is no longer on the table,” said Rand. Tam sensed a well-finessed fear but he’d reminded her that there was something practical he could do. She suggested he drink a Scary Mary. That was the new designation of Rand’s medicine: a cocktail made from fruit juice with a high percentage of chilli sauce. Like a Bloody Mary, but without the alcohol and scary to drink. It would not cure him but it would help him stay human longer. In the final hours of Caleb’s infection, he had only been coherent when he ingested chilli in one form or another.

Since the shift in the Cause, Varsity’s property value had seriously dropped. Animated corpses were popping up everywhere. Rand did as he was told and thumped through a few of them, though he seemed reluctant to commit to it fully. Tam needled him about being too precious with his Lexus. “If anything shatters the windscreen, we’re going to be pretty exposed,” said Rand. Good point.

There was one Wreck moving the opposite direction to the Mecca of the Cause. Tam shivered when she cottoned on that this was not a Wreck at all. It was somebody who had been infected recently. He was bloody and haggard but the Wrecks ignored him. He was hobbling out of No-Man’s Land. Maybe hoping to reach the METMA Centre. She thought about telling Rand to stop. But what would they do? Bring him back to the place he’d just escaped? Abandon their mission for a man they knew they couldn’t save? No. She swallowed her guilt and said nothing.

They eventually found Caleb with a tidy group of three other Wrecks. She let a choked “Oh, shit,” slip out. He was the archetypal zombie now.

For one thing, his arms were stained to the elbow with dark, dried blood. Possibly the dog’s. He had also picked up three severe slashes to his back and shoulder. Bluish Epsilon Rex blood had oozed out and soaked his shirt, which was ripped to bits.

“He’s been busy,” said Rand.

The group looked towards them. Rand recklessly cruised ahead, not changing his pace. Tam put her hands inside the poncho. With her elephant mask on, she hopefully looked nothing like prey.

The Wrecks watched them steadily as the car approached. They looked in the window like undead cops. But they didn’t turn into grabbing, violating monsters. Tam’s heart pounded like firecrackers in a bucket. Caleb glanced at her and she winced. His eyes were demonic. His face, hair and body were messed up like a child who’s been fighting in the dirt.

Rand pulled over halfway down the block. “Okay, then,” he said. “Stakeout.”

They watched him in the mirrors. Tam was fascinated by the surreal scene. They acted like monkeys. No, not monkeys… something about their repetitive behaviour was like insects, or robots. They looked around and felt the air, checked in with each other and then glided forward a few steps before repeating the process.

“So, how did he kill the dog?” said Rand. They inched forward, keeping pace with the Wrecks.

“I wish I knew,” said Tam.

“I do,” Rand said casually. “By absorbing the experience of the guy who went before him. Genetic memory. That’s how they learn.”

Tam reeled. “How long have you known this?” she demanded.

“About thirty seconds,” said Rand. He smiled.