Nanny sat back at the end of it and stared at the ceiling for a while.
'Why should we believe her?' she said eventually.
'Because she's me.'
'They do say that inside every fat girl is a thin girl and-' Nanny began.
'Yes,' said Agnes bitterly. 'I've heard it. Yes. She's the thin girl. I'm the lot of chocolate.'
Nanny leaned towards Agnes's ear and raised her voice. 'How're you gettin' on in there? Everything all right, is it? Treatin' you all right, is she?'
'Haha, Nanny. Very funny.'
'They were saying all this stuff about drinkin' blood and killin' people and everyone was just noddin' and sayin', 'Well, well, how very fascinatin"?'
'Yes!'
'And eatin' garlic?'
'Yes!'
'That can't be right, can it?'
'I don't know, perhaps we used the wrong sort of garlic!'
Nanny rubbed her chin, torn between the vampiric revelation and prurient curiosity about Perdita.
'How does Perdita work, then?' she said.
Agnes sighed. 'Look, you know the part of you that wants to do all the things you don't dare do, and thinks the thoughts you don't dare think?'
Nanny's face stayed blank. Agnes floundered. 'Like... maybe... rip off all your clothes and run naked in the rain?' she hazarded.
'Oh, yes. Right,' said Nanny.
'Well... I suppose Perdita is that part of me.'
'Really? I've always been that part of me,' said Nanny. 'The important thing is to remember where you left your clothes.'
Agnes remembered too late that Nanny Ogg was in many ways a very uncomplicated personality.
'Mind you, I think I know what you mean,' Nanny went on in a more thoughtful voice. 'There's times when I've wanted to do things and stopped meself...' She shook her head. 'But... vampires... Verence wouldn't be so stupid as to send an invitation to vampires, would he?' She paused for thought. 'Yes, he would. Prob'ly think of it as offering the hand of friendship.'
She stood up. 'Right, they won't have left yet. Let's get straight to the jelly. You get extra garlic and a few stakes, I'll round up Shawn and Jason and the lads.'
'It won't work, Nanny. Perdita saw what they can do. The moment you get near them you'll forget all about it. They do something to your mind, Nanny.'
Nanny hesitated. 'Can't say I know that much about vampires,' she said.
'Perdita thinks they can tell what you're thinking, too.'
'Then this is Esme's type of stuff,' said Nanny. 'Messing with minds and so on. It's meat and drink to her.'
'Nanny, they were talking about staying! We have to do something!'
'Well, where is she?' Nanny almost wailed. 'Esme ought to be sortin' this out!' 'Maybe they've got to her first?'
'You don't think so, do you?' said Nanny, now looking quite panicky. 'I can't think about a vampire getting his teeth into Esme.'