Up at the window, Tess cringed. That was going too far. If this didn't work, Kevin was going to look like a complete idiot. For a moment she was glad that she hadn't acknowledged him. Below her, Uncle Maurice said to Aunt Deirdre, 'Pure nutcase.' Beside her, Orla was staring, wide-eyed.

'Who is he?' she said. 'What is he going to do?'

'I don't know,' said Tess. But the next moment, Kevin demonstrated. He began to play the whistle, fairly tunelessly, and at the same time he began to call.

The part of Tess's mind that was and would always be rat tuned in instantly to the powerfully projected images; images that no ordinary human mind could receive. She was reminded that before Kevin reached the age of fifteen and lost the ability to Switch, he had spent more of his time being a rat than being a human being. His mastery of their visual language was total; far better than hers, and the messages he was sending were compelling.

'Out, out!' is what he was saying. 'Men coming with poisons, gases, traps. Rats dying in this place, rats dying in pain. Usguys leaving this place, huh? Huh? All of usguys leaving.'

Colm began to dance, clumsy in his Wellingtons, curly locks flopping over his eyes. A moment later, though Tess had not noticed she was gone, Orla appeared beside him and began to dance as well. Infected by their enthusiasm, Kevin started to hop and skip, and Tess was sure that his playing became better; even tuneful. But she didn't listen to it for long. Beneath its cheerful tootling the more serious communication was continuing.

'Rats waking up, quick, quick! Rats coming out into the daylight, escaping deadly danger behind, yup, yup.'

Tess could hear her aunt and uncle snickering downstairs inside the front door, but a moment later they went deadly quiet.

Because it was working. Sleepily, shaking themselves awake, the rats were beginning to emerge. They crawled out of the subterranean world beneath the farm, and appeared by ones and by twos in the yard. They scrambled and slithered their way down through the walls of the house, making so much noise that for an awful moment it seemed to Tess that the house was falling down around her. They surfaced from the drains in lengthening columns until suddenly the yard was flooding with rats, all blinking in the bright daylight and making their way towards the source of the urgent message.

Orla and Colm pointed and squealed in excitement, but they seemed unafraid and didn't stop dancing. Their views on rats, however, were clearly not shared by their parents. There was a blood-curdling shriek from the hall below as Aunt Deirdre realised what was happening, and a moment later, Uncle Maurice was striding across the yard, waving his arms around and making loud shooing noises. He swept Orla up under one arm and Colm under the other and carried them over to the oil tank, where Brian was already set up, enjoying a grandstand view of the action. Colm wriggled and kicked so hard that he lost one of his precious Wellingtons, but once he was parked up on the tank beside his brother and sister, he soon forgot about it.

For now Kevin had begun to move off; still playing his strident and unmusical trills, still repeating his urgent warnings in Rat, but adding now a bit of more encouraging information.

'New homes, happy rats. Green woods, rats rolling in hazelnuts, fat and healthy.'

In the shed where they were locked, Bran and Sceolan howled and scratched and rattled the door. From his perch on the apple tree the white cat watched intently as the rats flowed along the ground behind Kevin like the train of a royal robe. Now that they were fully awake they were more organised, though still extremely perplexed. Kevin stopped for a moment to get his bearings, trying to remember Tess's description of the crag from their conversation on the telephone. As soon as he saw it he recognised it, and took the most direct route towards it; straight over the wall and into the first of the meadows. The rats surged over behind him like a single, slithering creature, and then they were gone, leaving the yard empty except for Colm's fallen boot.

The three children had jumped down from the tank and were heading off in pursuit when Uncle Maurice intercepted them at the wall.

'It's dangerous,' he said. 'Them rats could get nasty.'

So they clambered back up on to the tank and watched as the boy from nowhere receded towards the grey hills, dragging a strange brown carpet behind him. Not until he had disappeared beyond the furthest wall of the farm did they come down, and look around, and find to their amazement that life was exactly as it had been before he came.

Tess was in the kitchen garden, helping her aunt with some weeding when Kevin came back to collect his bike and his gear. He waved across and held out his arms in a questioning shrug.

She communicated with him in Rat so that no one else would know what she said. 'Morning, huh?'

'Morning, yup, yup,' Kevin returned. 'Tent in the trees, near the road, near the hump-backed bridge. Us two drinking tea together.'

Aunt Deirdre was looking at Tess in a quizzical manner.

'That boy's back,' said Tess.

'So I see,' said her aunt.

They both looked across at him again and, without her aunt seeing, Tess winked.

'Maybe it was something he had on him in the way of a smell or some such,' said Uncle Maurice over dinner that evening. Since Kevin's visit he had been in great humour, and if he remembered the incident with the wild goats, he did not mention it.

'I think it was that whistle,' said Aunt Deirdre. 'You know the way there are some notes only dogs can hear. Maybe it's the same with rats.'

'Could be, I suppose,' said Uncle Maurice. 'Where is he from, would you say? Do you think he's a traveller?'

Aunt Deirdre had no opinion and the conversation ended. Tess looked around at her cousins. Beside her, Colm was putting his dinner away with no fuss or mess, taking the business of eating extremely seriously, as usual. Opposite, Brian was engaged in his daily ritual of hide-the-vegetables; a wasted effort, since soon his mother would notice and begin the daily ritual of eat-the-vegetables. Beside him Orla, the special child, the sickly one, could get away with eating or not eating, whatever she chose. What she was doing with her food, however, was of no interest to Tess. Orla's face was lit up with an inner light; she wore an expression of almost saintly bliss. Tess looked away before her cousin could catch her eye. She understood Orla's feelings but they made her uncomfortable nonetheless. For Orla, without doubt, saw Kevin's removal of the rats as a demonstration of magic; further proof that there was truth in fairy tales. And Tess had no way of letting her know the plain and simple truth.

CHAPTER EIGHT.

THAT NIGHT, TESS TOOK on rat form again and slid down through the walls of the house as she had done before. But unlike the previous night, the house was empty and silent. In the sitting-room a crumpled crisp packet smelt of heaven to her rat nose, but no one was there trying to get inside it. A few peanuts, dropped during the midnight movie, lay on the carpet beside the couch, untouched.

The kitchen was the same; empty and quiet. A new bar of soap sat beside the washing-up liquid on the draining board. Beneath the table half a dozen small cubes of cheese lay scattered on the floor, arousing a ferocious hunger in Tess's rat body and a strong sense of suspicion in her mind. There was something just a bit too neat about those blocks, as though they had been dropped there on purpose. What better test, after all, if her aunt and uncle wanted to find out whether or not there were any rats still around? So Tess denied her hunger and backed off, slipping underneath the sink and down through the floor into the drains. A moment later she was outside and testing the night air with her nose and her ears and her whiskers.

There was no sign of the cat, and the dogs were safely locked away. Tess scuttled along the wall of the house, then crossed the moonlit yard to the buildings. In the feed-shed, the smell of the dairy nuts threatened to unhinge her. It was almost more than she could do to deny herself, and she might have Switched to avoid the temptation if she hadn't encountered something unexpected. In the corner of the shed, close to the feed-bins, a single rat was snuffling around short-sightedly. Tess recognised him immediately as the old, one-toothed lad she had seen in the sitting-room the night before, having trouble with the fruit gums. Clearly he had missed Kevin's call; maybe because he was old and image-blind, maybe because his sleep was just too deep.

When he caught sight of Tess, the old rat jumped, then ran forward delightedly to greet her.

'Every place empty, huh?' he said. 'House empty, yard empty, heaps of food and no one eating it.'

'Yup, yup,' said Tess. 'Rats gone, rats in new home in the woods.'

The old gentleman twitched his whiskers and sniffed the air.

'Rats gone, huh? Us two all alone, huh?'

Tess's heart lurched. She didn't know how to answer. For it wouldn't be the two of them staying behind but just him, abandoned and bewildered, completely alone for what remained of his life. It was too sad to think about, so instead Tess got busy, collecting the broken nuts that the broom had missed that morning and heaping them in a dark corner where her old friend could eat in peace. It was almost more than her rat mind could bear, to gather food and not permit herself to eat it, but it was vitally important that the old gent didn't go chewing at bags or leaving any other sign that he had been there. She had to pull out all the stops.

When at last she had gathered all she could, she left her friend chewing away in quiet contentment, and slipped out under the door into the yard. Back in the house she became human again and, still in the grip of rat hunger, did a thorough job of raiding the fridge.

Tess dreamt the dream again; the one in which Kevin was a rat. She woke in terror and sat up in bed. It was already light and the birds were singing their loudest and most delighted songs, which they only did on bright, clear days. Tess sat up and looked out of the window, trying to shake off the fear which still gripped her heart. Everything out there was normal and safe. And she had a plan of some sort; some reason to get up.

When she remembered, enthusiasm rushed in and washed away the sense of dread. She had arranged to meet Kevin. Wasting no time, she slipped out of bed and gathered her clothes. It seemed that Orla really was asleep. But as Tess looked down at her in the bed, she saw something that brought the fear straight back. On top of the covers and wedged against the wall was a book which, presumably, Orla had been reading the night before. The t.i.tle was The Old G.o.ds: Story or History? Beneath the t.i.tle was a picture of a man, or something like a man, with antlers on his head. Tess turned away, but curiosity compelled her to turn back. The picture was just like the shadowy form that she had seen drifting through the woods the first time she had been there. She had a.s.sumed that she was imagining things, but if so, it was clear that she was not the only person who had imagined the same image. Why? Was it possible that such a being really did exist? With a shudder Tess tore her eyes away from it and crept out of the room.

She chose the kestrel again to find Kevin. The last time, she had been in a rush to see what Bran and Sceolan were up to, but now she could afford to explore the sensations of flight and the nature of the bird. Kevin had told her that another Switcher he had known had chosen a hawk as her permanent form when she reached fifteen. As she climbed into the heights Tess could easily understand why. The hawk was strong and clear-sighted. Tess always found the basic nature of animals and birds much simpler and less muddled than the complicated business of being human, but the hawk, above all others, had a purity of essence that was thrilling. The bird knew neither doubt nor hesitation; neither empathy nor remorse. Its eyes were designed for daylight but its heart belonged to the moon. Tess relished its sharp simplicity of being, and the knowledge that she might never experience it again made the sensations all the keener.

She could see the ground beneath her in the minutest detail. It wasn't at all like using binoculars; her sight didn't magnify the ground and make it seem nearer than it was. She just saw. She saw blades of gra.s.s, distant and tiny, bending beneath the weight of a stag beetle. She saw a bird tugging a worm from beneath a stone. She saw a matchbox toy, lost by some child many years ago and rusted now, barely visible among the gra.s.ses that had grown up over it.

Missing nothing, she climbed higher, widening her field of vision, scanning the landscape. She flew east and west, hovering occasionally to stabilise her vision, covering two or three square miles before the smell of smoke reached her and narrowed the search area. Eventually she found what she was looking for. Alerted by movement, she banked and overflew a stand of ash trees beside the narrow little bridge that Kevin had mentioned. Through the trees she could see the stretched dome of the tent and the resting spokes of the bicycle wheels. Delighted with herself, she dropped out of the sky, dodging through the branches at breakneck speed and coming to a hovering halt in the air, right in front of Kevin's nose.

Kevin jumped and took a step backwards, then realised who it was. He grinned and made a lunge at the bird, but she dodged out of his way and then Switched, judging the transition so perfectly that her feet met the ground as lightly as a feather.

'I keep forgetting you can do that,' said Kevin. 'Not fair.'

'Not for much longer, though,' said Tess.

Kevin nodded. 'Any plans?' he asked.

'No,' said Tess. 'It's driving me mad. What would you be if you had the decision ahead of you again?'

Kevin thought about it for a moment or two, then said, 'A rat. I always felt ... I don't know ... cheated, somehow. Because of being forced into a decision when it was time for me to choose. I'm sure that if I'd had a chance to think I would have decided on a rat.'

His words gave Tess an uncomfortable reminder of her dream, but she said nothing and Kevin went on, 'Maybe it doesn't make that much difference, in the end. I mean, the best thing was being able to Switch. Nothing could be as good as that, really, could it?'

Tess sighed. 'It's like having everything, isn't it?' she said. 'I can't stand the idea of losing it.'

Kevin had a neat little campfire going in front of his tent, carefully confined inside a ring of stones. On top of it a billy of water was coming to the boil.

'Tea?' he asked.

Tess sat down on a stone. As though it saw her, the smoke changed direction and drifted into her face. She waved her hands at it and waited. Sure enough, it soon returned to its previous course.

'Anyway,' said Kevin, dropping a fistful of tea leaves into the billy, 'what happened? How come you didn't warn them that I was coming?'

Tess groaned and related the story of Uncle Maurice and the wild goats. As she told it Kevin nodded, understanding and approving in a way that no one else ever did or could. Their friendship warmed her heart as it so often had in the past. As time went on it became more valuable, not less, no matter how different their lives appeared to be.

In the silence that followed the end of Tess's account, Kevin rooted around in his rucksack and found another cup. Tess watched him. He was still as tough and as scruffy as the town rats which had been his main companions during his Switcher days. He would never fit into normal human society, not in a million years. In a sudden, uninvited leap of imagination, Tess saw him as an old tramp, a bag man rummaging around on the edges of society; a human rat, unloved and unwanted. She had seen people like that, adrift on the city streets. They existed without the anchors that kept most people stable: family or education or job. Tess wondered whether their minds drifted in the same way, untethered, unfocussed, unaware of time.

'Maybe it's best to leave it that way,' said Kevin.

Tess came back to reality with a jolt. 'What?'

'No need to tell them now that you know me, is there?'

'No,' said Tess. 'In fact it would be a bit awkward, since I didn't say anything yesterday.'

Kevin used a grimy T-shirt to protect his fingers from the heat of the billy as he poured the tea into two battered enamel mugs.

'Trouble is, though,' Tess went on, 'I won't be able to invite you to my birthday party.'

'Are you having one?'

Tess shrugged. Kevin spooned milk powder into the cups. 'We can have one,' he said. 'Just you and me. A midnight one.'

'That would be good,' said Tess. 'That would make everything easier.'

'It's a date, then,' said Kevin, then blushed. 'I don't mean that kind of a date. I mean ...'

Tess laughed, but she could feel herself colouring as well. For a moment each of them struggled separately, trying to think of something normal to say. Tess got there first.

'What do the rats think of the woods?' she asked.

Kevin burst out laughing. 'They were very funny,' he said. 'They were like a coach-load of middle-aged tourists who have been brought to the wrong hotel.' He lapsed into fluent Rat as he continued. 'Feed-shed, huh, huh? Soap? Cupboards?'

Tess laughed.

'Usguys wet and cold,' Kevin went on. 'Usguys breaking our teeth on hazelnuts!'

If anyone had been watching through the trees they would have thought the two friends were quite mad, sitting in silence and laughing at nothing at all. But they understood each other perfectly.

'Blackberries sour! Yeuch! Hard work hunting, hard work making new nests!'

Tess could visualise them; fat pampered house rats, amazed at the lives their forerunners led, returning with the utmost reluctance to their wild roots.

'Will they stay, do you think?' she asked, returning to human speech.

Kevin nodded confidently. 'For a few generations at least. I painted a ferocious picture of Pestokill. They'll be telling their children and grandchildren about it. Like the bogeyman.'

Tess finished her tea but declined the breakfast that Kevin offered, not because the bread was squashed and the b.u.t.ter was full of grit but because she felt it would be better politics to make an appearance at the house.

'See you later,' she said.

Kevin was trying to cut the bread with a blunt knife, but he looked up when, a minute later, Tess was still standing there, as if undecided.

'You OK?' he asked.

Tess nodded. 'I was just wondering,' she said.

'Wondering what?'

'Did you see anything in the woods? Anything strange?'

'Not exactly. But there was a funny feeling about the place. I didn't really want to go in. Just left the rats at the edge like you suggested. Why?'

Tess shook her head. 'Just wondered.'

'Did you?' Kevin asked.

'I'm not sure,' she said. 'It was probably just my imagination. Maybe we could go there together some time?'

'All right by me,' said Kevin.

'It's a date, then,' said Tess.

Then, before Kevin could question her more closely, she Switched into a hawk again and sprang away into the sky.

CHAPTER NINE.