Of course, he had awoken before at a whole range of ages, three for example, eight and a half, and everything in between. There was nothing unusual about awakening, apart from the violent shaking. The bed was shaking. Violently. Like an airplane in turbulence. The whole room. Rippling and shuddering.

“Aaaaagh,” said Frederik, to see if he could, to make sure this wasn’t one of those dreams where he thought he was awake but really wasn’t. But sure enough the sound came out in a warble.

There had to be a sensible explanation and his next thought was an earthquake. But no earthquake had been recorded on Frederik’s Hill in the history of science, and Frederik knew his science, studied it diligently.
“It isn’t an earthquake,” he said, clinging grimly to all he knew. “It can’t possibly be.”

But even so, after eleven years of perfectly predictable nighttimes, Frederik had been shaken shockingly awake.

He was clearly some kind of tramp. There were holes in his gloves and stains on his pants and his shoes were quite unspeakable. Frederik quietly took a very tight grip on his backpack.
“I’m sorry,” he said, as he had been taught to do in such circumstances. “Not today, thank you.”

He averted his eyes and stepped aside and waited for the old man to shuffle off and worry someone else.
“Sorry?” the man growled, leaning close with his terrible breath. It was all Frederik could do not to gag. “You’ll be sorry when her zombies rise from the bowels of the Hill!”
“Zombies?” said Frederik, alarmed.
“Lurking in the darkness. Legions of them. They will gut you like dogs and sell your kidneys for castanets! You felt that earthquake. They have awoken! Get above ground! Board up the exits!”
He looked alarmingly directly at Frederik from terrifyingly close.
“It wasn’t an earthquake,” Frederik said.
“Of course it wasn’t! It was them!”

Now, maybe it was his sense of civic duty that led Frederik to hoist up his foot and let her bunk him over, or maybe it was the worry that he would look a ninny if he was out-braved by a weird girl. But whichever it was, he found himself well and truly on the other side of the gates and the rules and any way back from the brink of the staircase plunging into the bowels beneath.

Pernille rested her hands on the top of the gate. “Down you go,” she said. “Call out if anything attacks you.”
“You’re not coming?” His voice was suddenly very small.
“Of course not. Someone has to keep an eye out for the police.”
“Police?”
“Naturally.”

He tried to breathe. “I can’t go down there alone.”
“Take it slowly," she said. "Step by step. Let your eyes adjust. And remember, if the earth begins to tremble, and pieces of masonry are raining about you, try to cover your head.”