"You say that there were electric lights at the power station," he began. "And the boy heard a humming sound?"

"Yes, sir."

"He saw a lorry. Unloading some sort of box?"

"Yes."

"And what conclusion have you drawn from all this, Mr Cole?"

"Matt couldn't see very much in the darkness, Sir Michael. But he said that the people carrying the box were wearing strange, bulky clothes. I wondered if they might have been radiation suits."

"You think that somebody is trying to start up Omega One?"

"It is a possibility."

"An impossibility, I'm afraid." He turned to Matt. "How much do you know about nuclear power, young man?"

"Not a lot," Matt answered.

"Well, let me tell you a bit about it. I'm sure you don't want a physics lesson, but you have to understand." Sir Michael thought for a moment. "We'll start with the nuclear bomb. You know, of course, what that is."

"Yes."

"A nuclear bomb contains devastating power. It can destroy an entire city as it did, in the last war, at Hiroshima. In tests in the Nevada Desert, a small nuclear bomb blew out a crater so deep, you could have fitted the Empire State Building into it. The power of the bomb is the energy released in the explosion. And that energy comes from splitting the atom. Are you with me so far?"

Matt nodded. If he had been at school his attention would have wandered already, but this time he was determined to keep up.

"A nuclear power station works in much the same way. It splits the atom in a metal called uranium but instead of producing an explosion, which is uncontrolled, the energy is released gradually in the form of heat. The heat is fantastic. It turns water into steam, which then drives the turbines of an electricity generator and out comes electricity. That's all a nuclear power station does. It turns heat into electricity."

"What's wrong with coal?" Matt asked.

"Coal, gas, oil... They're all too expensive. And one day they'll run out. But uranium is incredible stuff. One tiny piece of it, a piece you could hold in your hand, has enough power to keep a million electric heaters running non-stop for twenty-four hours."

"Except it would kill you ... if you held it in your hand," Richard added.

"Yes, Mr Cole. The radiation would indeed kill you. Which is why, when uranium is moved, it is carried in heavy, lead-lined boxes."

"Like the box I saw!" Matt said.

Sir Michael ignored him. "At the heart of any nuclear power station is a nuclear reactor," he continued. "The reactor is basically a ma.s.sive concrete box a and it is in here that our controlled explosion takes place. The uranium is surrounded by long sticks called control rods. When you lift up the control rods, the explosion starts. And the higher you lift them, the more powerful the explosion becomes.

"The reactor is the most dangerous part of the station. You have to remember what happened at Chern.o.byl, in Russia. One mistake here and you risk what is known as an excursion, an explosion which might kill hundreds or even thousands of people and which would destroy a vast area of land for years."

Was that what they were planning, Matt wondered. Did Mrs Deverill and the other villagers want to commit some sort of act of terrorism? No. It made no sense. If that was the case, what did they want with him?

Sir Michael Marsh continued. "When the government began to think about building nuclear stations, fifty years ago, they set up a number of experimental stations where they could study reactors in action and make sure they were safe. Omega One was the first of these experiments and I helped design and build it. It ran for less than eighteen months. And after we'd finished with it, we shut it down and left it to rot in the pine forest that surrounds it."

"Maybe someone wants to get it running again," Richard persisted.

"They couldn't a for all sorts of reasons." Sir Michael sighed. "Let's start with the uranium. As I'm sure you know, you can't just buy uranium. Even dictators in countries like Iraq have found it impossible to get supplies. Let's suppose these villagers of yours owned a uranium mine. It still wouldn't help. How would they process the stuff? Where would they get the technical know-how and the resources?"

"But Matt saw something..."

"He saw a box. For all we know, it could have contained a picnic." Sir Michael glanced at his watch. "I last visited Omega One about twenty years ago," he said. "And there's nothing left inside. We removed anything that could possibly be dangerous when we dismantled the place. It was quite a job, I can tell you, transporting everything out of the wood."

"Why did you build it there?" Richard asked.

The scientist seemed momentarily thrown. "I beg your pardon?"

"Why did you build it in the middle of a wood?"

"Well, it had to be somewhere out of the way. And there's an underground river that runs through the wood. That was the main reason. A nuclear power station requires a constant supply of water, you see."

There was nothing more to be said.

"I'm sorry, Sir Michael," Richard said, as he got to his feet. "It seems that we've been wasting your time."

"Not at all. I've found what you and your young friend had to tell me most disturbing. At the very least, it would seem that somebody is trespa.s.sing on what is still government property and I shall certainly contact the appropriate authorities." He stood up. "Personally I wanted to knock the building down when we'd finished with it, but it was too expensive. As the minister put it, nature is the best demolition expert. However, let me a.s.sure you, you probably couldn't spark a decent fire in that damp old place, let alone a nuclear reaction."

Sir Michael showed them to the door. But before he opened it, he turned to Matt. "Are you interested in phillumeny?" he asked.

"In what?" Matt didn't know what he was talking about.

"The collecting of matchbox labels. I have almost a thousand of them." He pointed at a case on the wall. "The Tekka brand, made in India. And those are Russian. I think it rather wonderful that anything so ordinary can be so beautiful."

He opened the door.

"Do let me know how you get on," he said. "And I'll call when I've spoken to the police and tell you if there's any news."

Elizabeth Ashwood, the author of Rambles Around Greater Malling, lived in Didsbury, a suburb of Manchester. The address that Richard had been given took them to a detached house in a wide, leafy street. A gate and a path led through a garden that was perfectly neat, with an array of spring flowers. On the front door was a knocker shaped like a hand. Richard lifted it and let it fall. A hollow boom echoed through the house, and a minute later the door opened.

A thin, dark-haired woman stood there, not looking at them but past them, her eyes covered by two circles of black gla.s.s. Matt guessed she must be about thirty-five. He had never met a blind person before. He wondered what it must be like, living in perpetual night.

"Yes?" she asked impatiently.

"Hi." Richard smiled, unnecessarily. She couldn't see him, of course. "Are you Elizabeth Ashwood?" he asked.

"I am Susan Ashwood. Elizabeth was my mother."

"Was?" Richard couldn't keep the disappointment out of his voice.

"She died a year ago."

So that was it. They had come all this way for nothing. Matt was ready to turn round and go back to the car, but suddenly the woman spoke again. "Who are you?"

"My name is Richard Cole. I'm a journalist from the Greater Malling Gazette in Yorkshire."

"There are two of you."

"Yes."

How had she known? Matt hadn't made any sound.

"A boy..." Her hand reached out and somehow caught hold of Matt's arm. "Where have you come from?" she demanded. "Why are you here?"

Matt squirmed, embarra.s.sed to be held by her. "I've come from Lesser Malling," he said. "We wanted to know about a book your mother wrote."

"Come into the house," the woman said. "I can help you. But you must come in."

Matt glanced at Richard, who shrugged. The two of them went inside.

Miss Ashwood led them into a wide, airy corridor. The house was Victorian but had been carefully modernized with oak floors, concealed lighting and floor-to-ceiling windows. There were paintings on the walls a mainly expensive abstracts. Matt couldn't help wondering for whose benefit they were, since the owner couldn't see them. Of course, it was always possible that the woman had a husband and family. And yet at the front door he had got the impression that this was someone who was always alone.

She led them into a living room with low leather sofas and gestured at them to sit down. A polished grand piano, brilliant black, stood in the corner.

"Which of my mother's books brought you all this way?" she asked.

"It was a book about Lesser Malling," Richard said.

Matt decided to cut straight to the point. "We need to know about Raven's Gate."

The woman became very still. It was hard to read her emotions behind the black gla.s.ses but Matt could sense her excitement. "So you've found me..." she whispered.

"Do you know what it is?"

Susan Ashwood made no reply. The two black circles were fixed on Matt and he felt uncomfortable, wanting to move. He knew she could see nothing at all and wished she wouldn't stare at him in this way. "Is your name Matt?" she enquired.

"Yes."

"How did you know that?" Richard asked.

"I knew you would come," Miss Ashwood said. She was ignoring Richard. All her attention was focused on Matt. "I knew you would find me. It was meant to happen this way. I'm just glad you've arrived in time."

"What are you talking about?" Richard was getting angry. "I think we're at cross purposes," he went on. "We came to see your mother..."

"I know. She told me you'd seen her book."

"I thought you said she was dead?"

For the first time she turned to Richard. "You don't know who I am?"

"Sure." Richard shrugged at Matt. "You're Susan Ashwood."

"You haven't heard of me?"

"I don't mean to be rude, but should I have? Are you famous? What do you do? Do you play the piano?"

By way of an answer, the woman fumbled on a table beside the sofa. She picked up a business card and handed it to Richard. He turned it over and read: "You're a medium."

"What?" Matt asked.

"Miss Ashwood talks to ghosts," Richard explained. "Or that's what she believes."

"I talk to the dead in just the same way that I am talking to you now. And if you could hear them, you would know that there is a great upheaval in the spirit world. Terrible things are about to happen. Indeed they are already happening. That is what brought you here to my house."

"What brought me to your house," Richard said, "was the M62 motorway from Leeds. And it looks to me like I was wasting my time." He stood up. "Let's go, Matt!"

"If you leave this room without hearing what I have to say, you will be making the greatest mistake of your life."

"That's what you say!"

"You are involved in something bigger and more incredible than anything you could imagine. Like it or not, you have begun a journey without knowing it, and there can be no going back."

"I'm going back right now," Richard said.

"You can make light of it, but you have no idea what is happening. I feel sorry for you, Mr Cole. Because, you see, there are two worlds. The world you understand and the world you don't. These worlds exist side by side, sometimes only centimetres apart, and the great majority of people spend their entire lives in one without being aware of the other. It's like living on one side of a mirror: you think there is nothing on the other side until one day a switch is thrown and suddenly the mirror is transparent. You see the other side. That was what happened to you the day you heard about Raven's Gate. Nothing can be the same for you any more. It's as I say. You have begun a journey. You must continue to the end."

"What exactly is Raven's Gate?" Matt asked.

"I can't tell you. I know how unreasonable it must sound, but you have to understand." Miss Ashwood took a deep breath. "I belong to an organization," she continued. "I suppose you might say we're a secret society. But I'd put it another way. I'd say we were a society that looks after secrets."

"You mean ... like MI6?" Richard muttered.

"We call ourselves the Nexus, Mr Cole. And if you knew more about us, who we are, what we represent, perhaps you'd be a little less sarcastic. But as much as I want to, I can't speak to you on my own. You have to come with me to London. There's a man you must meet. His name is Professor Sanjay Dravid."

"Dravid!" Matt knew the name. He'd heard it somewhere before.

"This is ridiculous," Richard insisted. "Why do you have to drag us all the way to London? Why can't you tell us what we want to know here and now?"

"Because I swore an oath that I would never talk about this with anyone. We all did. However, if you come with me to London, if you meet the Nexus, then we can help you. You want to learn about Raven's Gate? We'll tell you everything you want to know ... and more."

"And how much money will it cost us to join this Nexus?" Richard demanded.

Miss Ashwood sat upright in her chair and Matt could sense how angry she was. Her fists were clenched. When she spoke, her voice was utterly cold. "I know what you think of me," she began. "You imagine I'm some sort of con artist. I sit in this house and I try to frighten people, to cheat them out of money. I call myself a psychic so I must be a fraud. I tell stories about ghosts and spirits, and weak, gullible people believe me." She paused. "But the boy understands," she continued. She turned to face Matt. "You believe me, don't you, Matt? You know about magic. I felt your power the moment you came here. I have never felt such strength before."

"Where is Professor Dravid?" Matt asked.

"In London. I told you. If you won't come with me, at least give me your telephone number. Let him speak with you."

"I'm not giving my number to anyone," Richard said. "And I don't care what you say, Miss Ashwood. We came here with a simple question. If you're not going to give us an answer, we might as well leave."

"Professor Dravid is at the Natural History Museum in South Kensington. That's where you'll find him."

"Sure. We'll send you a postcard." Richard stood up and more or less dragged Matt out of the room.

The car was parked opposite the house. They got in and Richard searched in his pockets for the keys. Matt could see that he was rattled.