"DARREN!" DEBBIE squealed, throwing her arms around me.

"Debbie!" I whooped and hugged her hard.

My English teacher was Debbie Hemlock - my ex-girlfriend!

"You've barely changed!" Debbie gasped.

"You look so different!" I laughed.

"What happened to your face?"

"How did you become a teacher?"

Then, together: "What are you doing here?"

We stopped, wide-eyed, beaming madly. We were no longer hugging, but our hands were joined. Around us, my fellow students gawped as though they were witnessing the end of the universe.

"Where have..." Debbie started, then glanced around. Realizing we were the centre of attention, she let go of my hands and smiled sheepishly. "Darren and I are old friends," she explained to the class. "We haven't seen each other in..."

Again she stopped, this time with a frown. "Excuse us," she muttered, grabbing my right hand and roughly leading the way outside. Closing the door, she swung me up against a wall, checked to make sure we were alone in the hall, leant in close and hissed, "Where the hell have you been all these years?"

"Here and there," I smiled, eyes roving her face, stunned by how much she'd changed. She was taller too - even taller than me now.

"Why is your face the same?" she snapped. "You look almost exactly as I remember you. You've aged a year or two, but it's been thirteen years!"

"How time flies," I smirked, then stole a quick kiss. "Good to see you again, Miss Hemlock."

Debbie froze at the kiss, then took a step back. "Don't do that."

"Sorry. Just glad to see you."

"I'm glad to see you too. But if anyone sees me kissing a student..."

"Oh, Debbie, I'm not really a student. You know that. I'm old enough to be... Well, you know how old I am."

"I thought I did. But your face..." She traced the outline of my jaw, then my lips and nose, then the small triangular scar above my right eye. "You've been in the wars," she noted.

"You wouldn't believe it if I told you how right you are," I smiled.

"Darren Shan." She shook her head and repeated my name. "Darren Shan."

Then she slapped me!

"What's that for?" I yelped.

"For leaving without saying goodbye and ruining my Christmas," she growled.

"That was thirteen years ago. Surely you're not still upset about it."

"The Hemlocks can carry a grudge a long, long time," she said, but there was the glint of a smile in her eyes.

"I did leave you a going-away present," I said.

For a moment her face was blank. Then she remembered. "The tree!"

Mr. Crepsley and me had killed the mad vampaneze - Murlough - in Debbie's house on Christmas Eve, after using her as bait to lure him out of his lair. Before leaving, I'd placed a small Christmas tree by her bedside and decorated it (I'd drugged Debbie and her parents earlier, so they were unconscious when Murlough attacked).

"I'd forgotten about the tree," she muttered. "Which brings us to another point - what happened back then? One moment we were sitting down to dinner, the next I woke up in bed and it was late Christmas Day. Mum and Dad woke in their beds too, with no idea of how they got there."

"How are Donna and Jesse?" I asked, trying to avoid her question.

"Fine. Dad's still travelling the world, going wherever his work takes him, and Mum's started a new... No," she said, prodding me in the chest. "Forget what's been going on with me. I want to know what's up with you. For thirteen years you've been a fond memory. I tried finding you a few times, but you'd vanished without a trace. Now you waltz back into my life, looking as though the years had been months. I want to know what gives."

"It's a long story," I sighed. "And complicated."

"I've got time," she sniffed.

"No, you haven't," I contradicted her, nodding at the closed classroom door.

"Damn. I forgot about them." She strode to the door and opened it. The kids inside had been talking loudly, but they stopped at the sight of their teacher. "Get out your books!" she snapped. "I'll be with you presently." Facing me again, she said, "You're right - we don't have time. And my schedule's full for the rest of the day - I've a teachers' meeting to attend during lunch. But we have to get together soon and talk."

"How about after school?" I suggested. "I'll go home, change clothes, and we can meet... where?"

"My place," Debbie said. "I live on the third floor of an apartment block. 3c, Bungrove Drive. It's about a ten-minute walk from here."

"I'll find it."

"But give me a couple of hours to correct homework," she said. "Don't come before half-six."

"Sounds perfect."

"Darren Shan," she whispered, a small smile lifting the corners of her mouth. "Who'd have believed it?" She leant towards me, and I thought - hoped! - she was going to kiss me, but then she stopped, adopted a stern expression and pushed me back into class ahead of her.

The lesson passed in a blur. Debbie tried hard not to pay special attention to me, but our eyes kept meeting and we were unable to stop smiling. The others kids noted the remarkable bond between us and it was the talk of the school by lunchtime. If the students had been suspicious of me at the start of the day, now they were downright wary, and everyone gave me a wide berth.

I breezed through the later classes. It didn't bother me that I was out of my depth and ignorant of the subject matter. I no longer cared or tried to act clued up. Debbie was all I could think about. Even when Mr. Smarts threw my maths copy at me in science and bawled furiously, I only smiled, nodded and tuned him out.

At the end of the day I rushed back to the hotel. I'd been given the key to a locker, where I was supposed to leave my books, but I was so excited I didn't bother with it, and carried the full bag of books home with me. Mr. Crepsley was still in bed when I arrived, but Harkat was awake, and I hurriedly told him about my day and meeting Debbie.

"Isn't it wonderful?" I finished breathlessly. "Isn't it incredible? Isn't it the most..." I couldn't think of any way to describe it, so I simply threw my hands into the air and yelled, "Yahoo!"

"It's great," Harkat said, wide mouth spreading into a jagged smile, but he didn't sound happy.

"What's wrong?" I asked, reading the unease in his round green eyes.

"Nothing," he said. "It's great. Really. I'm thrilled for you."

"Don't lie to me, Harkat. Something's bugging you. What?"

He came out with it. "Doesn't this seem a bit... too coincidental?"

"What do you mean?"

"Of all the schools you could have gone to... all the teachers in the world... you end up at the one where your... old girlfriend's teaching? And in her class?"

"Life's like that, Harkat. Strange things happen all the time."

"Yes," the Little Person agreed. "And sometimes they happen... by chance. But other times they're... arranged."

I'd been unbuttoning my shirt, having slipped off my jumper and tie. Now I paused, fingers on the buttons, and studied him. "What are you saying?"

"Something smells rotten. If you'd run into Debbie in the street, that... would be something else. But you're in her class at a school where... you shouldn't be. Somebody set you up to go to Mahler's, someone who... knows about Murlough, and about your past."

"You think the person who forged our signatures knew Debbie was working at Mahler's?" I asked.

"That's obvious," Harkat said. "And that in itself is cause for worry. But there's something else we... must consider. What if the person who set you up didn't... just know about Debbie - what if it was Debbie?"