I followed the girl as best I could, though she moved with surprising speed – despite never seeming to break into a run – and I was hampered by my rucksack. I felt glad that the moon, almost full, had appeared from behind the cover of clouds. By its light I could see well enough to avoid falling over.

In what seemed no more than a few minutes we arrived at a place where a couple of hardy trees grew out of the mountain. The girl slowed to a stop, reached out and pulled aside a curtain of branches, revealing a dark hole leading into the mountain. I wondered if we were going in, but then I heard the scuffle of footsteps, and Henry emerged.

Unusually for HH, he looked a bit the worse for wear. He had cobwebs and leaves in his hair, his jacket was torn at the shoulder and I spotted a cut on the side of his face that oozed a trickle of blood.

“That was impressive,” Henry said, beaming. “How did you know the passage was there?”

The girl narrowed her eyes as if she didn’t particularly like what she saw. “I live around here, silly boy,” she said simply.

“Well, thanks anyway.” Henry stuck out a hand. “My name’s Henry, by the way, and this is Dolf.”

“Bella,” snapped the girl, ignoring Henry’s proffered handshake. “You shouldn’t be in this place after dark. It’s not safe.”

“You mean, because of the vampires?” said Henry, his voice steady.

The girl hesitated before she answered, and I thought I saw a gleam of laughter in her eyes. “Many different kinds of creature live in these mountains,” she said, avoiding the question. “It is not wise to be out here.”

“You don’t seem to mind,” said Henry.

I glanced between the two of them, not sure where this conversation was going.

Bella frowned. “That’s because I know the place and the place knows me. My family have lived around here for a long time.”

“Well, in that case, do you have any idea what this means?” Henry pulled a crumpled piece of paper from his pocket. As he passed it over I caught a glimpse of a roughly-sketched drawing. It depicted people with either spears or swords attacking a huge worm-like creature with a long spiked tail that spat fire.

Bella’s reaction was instant. Her face clouded with anger and she rattled off a whole series of sentences in what I assumed was Rumanian. Then, not knowing Henry was actually pretty fluent, she seemed to realise who we were and switched to English.

“Where did you find those?” she demanded, staring so hard at Henry that I thought he might actually burst into flames.

Of course HH wasn’t fazed. “They were scratched onto the walls of the well shaft,” he said. “While I was down there I copied them. I thought they might be useful.”

“Useful for what?” said the girl.

“It’s a long story,” answered Henry.

Bella folded her arms and continued her stare. In the moonlight her eyes seemed to glow again. “So tell me,” she said.

I could see Henry weighing up whether or not to be truthful. I have to admit I was quite surprised when he told her how our journey began, with the Unbelievable Times article. Henry sketched our adventures briefly, and when he mentioned Whitby Bella’s eyes flickered – she clearly recognised it, but said nothing. But I noticed he did not mention the mysterious attackers in Whitby, or the strange events at the restaurant yesterday.

When he finished, Bella stared at him in silence for a moment. Then she looked away, up towards the castle and then at the moon, which was lower in the sky now.

“It will be dawn soon. I must go home.” She looked at both of us intently and said, “You should not be here. It is not safe. Go back where you came from.”

“I’m afraid we can’t do that – not till we find out what’s going on.” Henry fixed his eyes on her. “Why have you been following us?”

Good old Henry, direct as ever.

At first I thought Bella wasn’t going to answer. Then she suddenly laughed, a surprisingly pleasant sound in the darkness.

Just as quickly, she went back to frowning again.

“I was curious. Two English boys, wandering about my country, asking questions about vampires. Coming up here, after dark, alone. You are either very stupid or very brave – I cannot decide which.”

Henry flashed his famous grin, and pushed his hair back from his brows. “So what can you tell us about the pictures at the bottom of the well?” he asked.

“Not now,” replied Bella. “It is better for us all if we leave this place.” She seemed a bit uneasy and kept glancing at the sky as if looking for something.

“I will guide you down the mountain to the road,” she continued. “I hope your man with the car will return for you at dawn.”

“Perhaps we can talk later?” Henry persisted.

“Perhaps,” Bella responded, glancing at the sky again.

Maybe because we were going downhill or perhaps because Bella knew the way better than us, we were soon standing by the roadside. There was no sign of Mr Antonescu. I wasn’t surprised. I glanced at my watch – it was almost four a.m. Suddenly I felt tired. We had been on the mountain for most of the night and at that moment the idea of a shower, a hot chocolate and a warm bed seemed more important than solving any mystery.

“Take my advice. Go away from this place,” the girl said to us again.

Then she was gone, so suddenly that neither of us could see where or how she went.

“Well, she wasn’t very friendly,” I said.

“I’m pretty sure she doesn’t get out much,” answered Henry thoughtfully. “Did you notice the strange dialect of Rumanian she spoke when she got angry? Really old-fashioned. A bit like if you or I spoke medieval English.”

I was still thinking that a) I had no idea what dialect the girl spoke, and b) how weird it would be if HH and I started spouting some old language, especially as I was pretty terrible at anything other than basic English, when there was a sudden rush of footsteps. Before we could react, about a dozen dark figures surrounded us. I tried to stay calm even as I noticed they all had nunchuks in their hands and one carried what looked like a rather big knife.

Not this lot again, I thought, steeling myself for a repeat of the punching and kicking we’d received in Whitby.

But to my surprise we were spared, because a brilliant light suddenly illuminated the scene, accompanied by a noise loud enough to wake any un-dead vampires who might have been hanging around. I just had time to see that the girl who’d just left us was straddling a large black motorbike before all hell broke loose.

The bike skidded to a stop and Bella leapt gracefully from the saddle, leaving the engine running. She hit the group of startled attackers like a sledgehammer, scattering them in all directions. Cries. Yells. Screams. Henry and I just stood there staring as the slender girl waded into the gang like a knife into a block of cheese.

It was then that both they and we spotted Bella’s fine set of fangs, and eyes that blazed with light.

In the heat of the realisation, I couldn’t help but shout out, “She’s a vampire!”

The attackers who were still standing saw Bella’s face clearly in the light from her motorbike, and they reacted exactly as you’d expect. More cries. More screams. More yells. I distinctly heard one man shout, “The Count’s daughter is among us!” Then they fled, with those who could racing away, and those who’d received Bella’s punches and kicks limping or staggering off into the darkness.

As quickly as it began, the attack was over. Bella returned to her bike, hauled it on to its stand and switched off the engine. The night was suddenly very quiet, though I could almost hear Henry’s mind ticking over as he struggled to decide what to ask about first.

In the end he settled on a rather shaky, “Thank you. That’s twice you’ve saved us.”

Bella shrugged. “I told you to go home,” she said. The fangs had vanished – withdrawn, just like in the movies – and her eyes were clear blue again. I found this comforting since I assumed it meant we were not about to be attacked, but at the same time I saw again the small trickle of blood on Henry’s face.

Bella must have caught me looking, because she began to laugh. “Don’t worry,” she said. “I won’t attack you. I gave all that up two hundred years ago.”

Henry and I both chuckled – a bit hysterically – while Bella leaned against her bike and studied us seriously.

“Who exactly are you?” Henry managed at last.

“Bella Dracul,” she answered without hesitation. “The only daughter of Prince Vlad Dracula.”

I goggled, trying to take this in. I had no doubt she was telling the truth. Meanwhile Henry’s logical mind kicked in.

“I thought vampires couldn’t have children.”

“My father was not always a vampire,” returned Bella.

“But…” I just about found my voice as questions still ran around my head.

“It is a mistake everyone makes. Tourists! Film people! What do they know? Always coming here in search of clues.”

“You mean there was another vampire before Dracula?” I asked.

“Of course. Many more. All of them are gone now. Or else are in hiding, like me.”

Henry was surprisingly quiet, but I had been doing the maths. “If you’re Vlad Dracula’s daughter you must be… over five hundred years old!”

Bella tossed her head. “Don’t you know it’s rude to ask a girl her age?” she said with a smile, then her eyes turned serious. “I was born in 1461, not far from here. My mother was a mortal, like my father at that time. It was only later that he…” She paused, as if she didn’t want to say the words.

“You mean that your father… made you a vampire?” said Henry, breaking the silence.

Bella gave a quick nod, and I thought I detected something like sadness on her pale face. She looked up at the sky again. The first edge of greenish light was creeping above the mountains. “I must be gone from here. It will be dawn soon and that at least is one story that’s true – my kind cannot be out in sunlight. But don’t worry, I do not think those people will be back in a hurry. I will come to you tomorrow night and we will talk some more.”

And with that the girl who was Dracula’s daughter climbed back onto her bike, started the engine and roared off into the night.