"It was not his place," Mr. Crepsley said. "As your mentor, I am responsible for informing you. I am sure he would have told me about it, so that I could have sat down with you and explained it, but there was no time — Mr. Tiny arrived and we had to leave the Mountain."

"You said Darren would grow during… the purge," Harkat said. "How much?"

"There is no telling," Mr. Crepsley said. "Potentially, he could mature to adulthood in the space of a few months — but that is unlikely. He shall age a few years, but probably no more."

"You mean I'll finally hit my teens?" I asked.

"I would imagine so."

I thought about that for a while, then grinned. "Cool!"

But the purge was far from cool — it was a curse! Shaving off all the hair was bad enough — Mr. Crepsley used a long, sharp blade, which scraped my skin raw — but the changes my body was undergoing were much worse. Bones were lengthening and fusing. My nails and teeth grew — I had to bite my nails and grind my teeth together while I walked at night to keep them in shape — and my feet and hands got longer. Within weeks I was five centimetres taller, aching all over from growth pains.

My senses were in a state of disarray. Slight sounds were magnified — the snapping of a twig was like a house collapsing. The dullest of smells set my nose tingling. My sense of taste deserted me completely. Everything tasted like cardboard. I began to understand what life must be like for Harkat and made a resolution never to tease him about his lack of taste buds again.

Even dim lights were blinding to my ultra-sensitive eye. The moon was like a fierce spotlight in the sky, and if I opened my eyes during the day, I might as well have been sticking two fiery pins into them — the inside of my head would flare with a metallic pain.

"Is this what sunlight is like for full-vampires?" I asked Mr. Crepsley one day, as I shivered beneath a thick blanket, eyes shut tight against the painful rays of the sun.

"Yes," he said. "That is why we avoid even short periods of exposure to daylight. The pain of sunburn is not especially great — not for the first ten or fifteen minutes — but the glare of the sun is instantly unbearable."

I suffered with immense headaches during the purge, a result of my out-of-control senses. There were times when I thought my head was going to explode, and I'd weep helplessly from the pain.

Mr. Crepsley helped me fight the dizzying effects. He bound light strips of cloth across my eyes — I could still see pretty well — and stuffed balls of grass into my ears and up my nostrils. That was uncomfortable, and I felt ridiculous — Harkat's howls of laughter didn't help — but the headaches lessened.

Another side-effect was a fierce surge of energy. I felt as if I was operating on batteries. I had to run ahead of Mr. Crepsley and Harkat at night, then double back to meet them, just to tire myself out. I exercised like crazy every time we stopped — push-ups, pull-ups, sit-ups — and usually woke long before Mr. Crepsley, unable to sleep more than a couple of hours at a time. I climbed trees and cliffs, and swam across rivers and lakes, all in an effort to use up my unnatural store of energy. I'd have wrestled an elephant if I'd found one!

Finally, after six weeks, the turmoil ceased. I stopped growing. I didn't have to shave any more (though the hair on my head remained — I was no longer bald!). I removed the cloth and grass balls, and my taste returned, although patchily to begin with.

I was about seven centimetres taller than I'd been when the purge hit me, and noticeably broader. The skin on my face had hardened, giving me a slightly older appearance — I looked like a fifteen- or sixteen-year-old now.

Most importantly — I was still a half-vampire. The purge hadn't eliminated my human blood cells. The downside of that was I'd have to undergo the discomfort of the purge again in the future. On the plus side I could continue to enjoy sunlight for the time being, before having to abandon it forever in favour of the night.

Although I was keen to become a full-vampire, I'd miss the daytime world. Once my blood turned, there was no going back. I accepted that, but I'd be lying if I said I wasn't nervous. This way, I had months — perhaps a year or two — to prepare myself for the change.

I'd outgrown my clothes and shoes, so I had to stock up at a small human outpost (we were leaving civilization behind again). In an army surplus shop, I chose gear similar to my old stuff, adding a couple of purple shirts to my blue ones, and a dark green pair of trousers. As I was paying for the clothes, a tall, lean man entered. He was wearing a brown shirt, black trousers and a baseball cap. "I need supplies," he grunted at the man serving behind the counter, tossing a list at him.

"You'll need a licence for the guns," the shopkeeper said, running an eye over the scrap of paper.

"I've got one." The man was reaching into a shirt pocket when he caught sight of my hands and stiffened. I was holding my new clothes across my chest, and the scars on my fingertips — where I'd been blooded by Mr. Crepsley — were clear.

The man relaxed instantly and turned away — but I was sure he'd recognized the scars and knew what I was. Hurrying from the shop, I found Mr. Crepsley and Harkat on the edge of town and told them what had happened.

"Was he nervous?" Mr. Crepsley asked. "Did he follow when you left?"

"No. He just went stiff when he saw the marks, then acted as though he hadn't seen them. But he knew what the marks meant — I'm certain of it."

Mr. Crepsley rubbed his scar thoughtfully. "Humans who know the truth about vampire marks are uncommon, but some exist. In all probability he is an ordinary person who has simply heard tales of vampires and their fingertips."

"But he might be a vampire hunter," I said quietly.

"Vampire hunters are rare — but real." Mr. Crepsley thought it over, then decided. "We will proceed as planned, but keep our eyes open, and you or Harkat will remain on watch by day. If an attack comes, we shall be ready." He smiled tightly and touched the handle of his knife. "And waiting."

BY DAWN we knew we had a fight on our hands. We were being followed, not just by one person, but three or four. They'd picked up our trail a few kilometres outside the town and had been tracking us ever since. They moved with admirable stealth, and if we hadn't been anticipating trouble, we might not have known anything was amiss. But when a vampire is alert to danger, not even the most fleet-footed human can sneak up on him.

"What's the plan?" Harkat asked as we were making camp in the middle of a small forest, sheltered from the sun beneath the intertwining branches and leaves.

"They will wait for full daylight to attack," Mr. Crepsley said, keeping his voice low. "We will act as though all is normal and pretend to sleep. When they come, we deal with them."

"Will you be OK in the sun?" I asked. Though we were sheltered where we were, a battle might draw us out of the shade.

"The rays will not harm me during the short time it will take to deal with this threat," Mr. Crepsley replied. "And I will protect my eyes with cloth, as you did during your purge."

Making beds amid the moss and leaves on the ground, we wrapped ourselves in our cloaks and settled down. "Of course, they might just be curious," Harkat muttered. "They could simply want to see… what a real-life vampire looks like."

"They move too keenly for that," Mr. Crepsley disagreed. "They are here on business."

"I just remembered," I hissed. "The guy in the shop was buying guns!"

"Most vampire hunters come properly armed," Mr. Crepsley grunted. "Gone are the nights when the fools toted only a hammer and wooden stake."