'Nothing you'd like to eat,' he snapped.

'I don't always eat mud.'

'I'm not talking about mud.'

'Look, what's your name?'

He paused. 'My name?'

'Can't you remember it, either?'

'I've got it back now, but it doesn't feel as if it belongs to me.' He gave a grim smile. Those gold-tipped incisors glinted. 'For the record, I'm called Carter.'

'Why the record?'

'Names don't mean anything round here.'

'They do to me. I'm April Connor.' She held out her hand. 'Mr Carter.'

He stared at her hand. 'Carter Vaughn. No mister. Still hungry?'

She nodded. 'To the point of nausea.'

'They all get like that, April.' He shook her hand. 'That's why you ate dirt, and the others ate stones, then they decided that the big guy should become dinner.'

'Why did they choose him?'

'Juiciest. Start walking.'

She walked in silence for a moment until they reached another sh.o.r.eline. This one was deserted; the falling tide revealed a stretch of sand that ran out a hundred yards or so. The pains in her stomach flared up again. A sickening spasm that fluidly transformed itself into raging hunger that attacked her veins as much as her stomach.

April talked to distract herself from the hunger. 'What's this place called?'

'As far as I know it doesn't have a name.' When he saw the anxiety in her face he smiled. 'Okay, I know you want answers. I call it Willow Island. On account ofa' He pulled at the fronds of a willow. 'And Rat Island would do. There's hundreds of the little b.u.g.g.e.rs.'

'I've been calling it the Isle of the Dead.' She rubbed her stomach. 'It seemed apt.'

'Yeah, that's a good one, too.'

'But how did I end up out here in the ocean?'

'Ocean? This is the River Thames. When it's daylight you can make out Gravesend upstream.'

The vastness of the twinkling water astounded her. 'But it's huge. I can't see the bank.'

'That's because it's low-lying. Also we're down near the end of the estuary. Is it getting bad?'

'Uh?'

'The hunger?'

She pressed her lips together as she nodded. Images of cooked meats seared through her - chops, steaks, rib roast, hams, hamburgers, you name it.

'This is when mud starts looking like Sunday dinner, doesn't it?'

Again she could only nod as painful cramps snapped her stomach muscles tight. In another effort to distract her she spat out another question. 'How did we get here, Carter?'

'You know how, April. You know exactly how.'

'I was attacked. Thrown in the rivera from the embankment near Westminster.' She found it hard to speak, the pain was so intense. 'You?'

'You were bitten on the waist. See the bite mark on my wrist? I thought I was helping some homeless kid in a park. He nearly chewed my hand off, then dumped me in the water at Woolwich. I drifted down with the tide like the rest.'

'I don't understanda' The pain grew worse.

'What is there to understand? It's the way it is. All we can do is keep away from the headcases, they get so hungry they'll eat anything. See those teeth marks in the tree trunk?'

April eyed the trunk of the willow. The bark resembled bacon - or at least it did right then. She saw how satisfying it would be to sink her teeth into the flesh of the tree.

'Don't try it.' Carter guessed what she was thinking. 'You'll only break your teeth.'

'But I've got to eat,' she said. 'I can't think properly. I need to bite down ona' She rubbed her forehead as nothing less than starvation ripped through her. 'Just to bite. That would be enough for now.' Even as she spoke she eyed the sand at her feet. Its sugary whiteness shining in the moonlight was so alluring she longed to gorge.

'Look at me, April. No, look into my face. Eating that c.r.a.p only makes you sick or snaps your teeth. I'll show you how to stop the worst of the hunger. It won't make it go away but it'll be tolerable. Understand?'

Reluctantly, she forced herself to stop ogling the crisp sand that offered nothing less than a whole feast beneath her feet.

'Listen,' Carter told her. 'First we'll deal with the hunger pains, then I'll tell you everything I know. Okay?'

'Okay. Tell me what I have to do.' By now, she found she couldn't take her eyes off the firm roundness of his Adam's apple.

Carter pointed at the pool of water left by the high tide. 'There,' he told her. 'Don't eat the mud or the sand, just drink as much as you can.'

'That puddle?' April Connor clutched her stomach. 'I need food!'

'You won't get what you want here. Drink that, it'll stop the pains.'

'b.l.o.o.d.y moron,' she hissed. 'That's river watera are you trying to poison me?'

'Your choice, April. Drink, or go back to those lunatics and eat each other; I've seen it all before.'

'There's been more of us?'

'Lots more. Usually they go so crazy they end up back in the water.'

They made their way down on to the sh.o.r.e that glinted with a series of tidal pools. The one that Carter had indicated was clear enough to reveal bits of broken gla.s.s in the bottom. There was a latex glove, too, with a finger and thumb missing. She fancied she could see some worm-like creatures squirming amongst the sludge.

'You want me to drink that!'

'It's the only way, April.'

'I can't.'

'You're different from the rest. You haven't gone crazy like them.'

'Maybea bettera uh, if I had.' Wild l.u.s.ts blazed through her. A rat scampered up the banking. Catch it! Don't bother killing it first. Devour it alivea 'Start drinking. If you don't it'll be too late. You lose self-control.'

'No. I'm not drinking out of a filthy puddle!'

'Your choice.' He backed away along the path, his hands held out at either side. 'Don't say I never tried to save you.'

The instant her will power collapsed she didn't so much get down on to her knees as attack the puddle. She hurled herself at it and began drinking. When the palms of her hands couldn't contain enough water she buried her face in it and sucked it straight into her mouth. What she thought would have been cold and bitter turned out to be warm and satisfying. As long as she drank, that is. The moment she stopped the hunger pangs slammed through her with so much force she gasped. So she relentlessly gulped down the water. This came from the estuary; it wasn't freshwater but partly saline. It was that saltiness that made the flavour so irresistible. The minerals in that blend of river and ocean had a pleasing tang. In her mind's eye she saw that solution of salt.w.a.ter spread through her veins to damp down those fires of rapacious hunger.

Carter crouched beside her. 'It's working, isn't it?' Quickly, he scooped handfuls of water to his own mouth. 'Every few hours you'll need to come back here and drink.'

Panting from the exertion of devouring pint after pint of water, she gasped, 'Why this stuff? Why does it work when eating mud doesn't?'

'If you fill your belly with water it tricks the mind into believing you've eaten. Mud only makes you sick.'

April sucked each finger in turn where the water had soaked them. 'It's the salt.' Her eyes fixed on those pools of estuary water left by the tide. 'If you drink straight from the river it doesn't have the same effect, does it?'

'No. Always stick with the tidal pools.'

'The liquid begins to evaporate leaving the salt behind. These are more intensely salinea' She paused. 'But why do we have a craving for salt?'

'We crave something that contains salt,' he told her.

'What's that?'

'It'll come to you.' As he stood up he continued licking his fingers. 'Come on.'

'Where now?'

'I want to show you something.'

'A boat would be nicea and food.'

'I've got neither. We're marooned here.'

'Mr and Mrs Robinson Crusoe.'

'Hey, you made a joke.' He smiled revealing the gold-tipped teeth. 'That proves you must be feeling better, yeah?'

'I'm wandering round a desert island in a torn dress, wearing one sandal; I've eaten mud and watched a man torn to pieces. I feel downright tickety-boo.'

He stopped and looked her in the eye. 'In my book that's feeling better. You're a million times better than those animals back there on the beach. They'll be sat chewing on that guy's face. Not that it'll help them. By morning they'll have gone mad with hunger and thrown themselves back into the river.'

'Why not show them your magic cure?'

'The tidal pools? They wouldn't listen. They've all disintegrated up here.' He tapped his head. 'I call them Berserkers. We're the only ones who are still functioning mentally.'

She became wary. 'So there'll just be me and you on the island?'

'Not quite. I'll introduce you to the rest of our family.'

'Family? I've no plans to stay here.'

'Okay.' He shrugged. 'But how are you going to leave?'

Once more April Connor found herself following this man, Carter Vaughn, through the clumps of willows.

'Best make it quick,' he told her. 'The sun will be rising soon.'

'Thank G.o.d. This has to be the longest night of my life.'

'Trust me, you won't like sunshine anymore.'

'Why?'

'Feel your hair,' Carter said.

'Uh. Yuk.'

'Sticky, isn't it?'

'It feelsa disgusting. I must have got something on it. Oil or tar.'

He shook his head. 'Mine's sticky too. We all have sticky hair.'

'I'll wash it in the river.'

'It won't do any good. It stays sticky, like you've rubbed syrup into it.'

'Why?'

'Because we've changed. I'm not the same Carter Vaughn anymore. You're not the same April Connor.'

'Oh, I'll be me again, once I get away from this island.'

'Okay, just you wait and see. Then you'll believe me.'

Carter made his way up a slight incline into a clump of thick bushes; he was hurrying as if time was running out.

April called after him, 'So, what's all this about sticky hair and not liking sunlight anymore? What's it all mean?'

He didn't look back. 'Hurry up. Before it starts to get light.'

So, what could she do? The man knew enough to stop her going crazy when the hunger pangs started. Maybe he had other information that would be useful. She plunged into the bushes after him. A bird screeched at being disturbed. Dark shapes flitted by her feet as rats fleda or were they circling behind her, ready to sink their incisors into her bare heels?