"Why? What did Ghastly tell you?"

"Something about streams of energy in the sky. A public display of power like that could very likely be another mortal developing magical abilities. Does that pique your curiosity?"

She considered. "No. But then I'm not easily piqued. I'll reserve judgement."

"That's all I ask."

They parked near the city centre and walked for a few minutes until they came to the apartment complex where Patrick Xebec lived. They were let in by Xebec's wife, a Frenchwoman with tired eyes.

"I was on the phone to him," she said. "We were talking about something, the neighbour's cat, and then he said there were these lights in the sky. He said they were energy streams. I told him to call the Sanctuary but he said you wouldn't get there in time. He said someone was going to notice and realise it wasn't just a light show. He told me he'd ring me back once he figured out what was going on. I... I haven't heard from him since."

"Do you know where he was when he saw all this?" Skulduggery asked.

"He was driving through Monkstown. But he said the energy streams were miles away. He didn't say what direction. Patrick has never gone more than a few hours without checking in, let alone three days. Something bad has happened to him, I know it." Her hand went to her mouth. "Please, Detective, find my husband."

"We'll do our best," Skulduggery said.

They walked back to the car and Valkyrie's arm started to ache. Skulduggery was talking about something that had just occurred to him, something to do with Greta Dapple.

"She mentioned that her birthday is this Saturday," he said, "which means it's May the first the start of summer. Coincidence? I don't think so. But what does Argeddion's old girlfriend have to do with mortals developing magic? What does she have to do with the Summer of Light?"

The ache was spreading, turning to a dull but persistent throb that Valkyrie could feel in her chest. The world flickered and she stopped walking, suddenly dizzy. "Whoa."

Skulduggery took her arm, steered her round the corner. "Valkyrie, look at me."

He flickered and the whole world vanished, just for the blink of an eye. Valkyrie staggered back against the wall. "What the hell is going on? Skulduggery? Everything's disappearing. What's wrong with-"

And then Skulduggery was gone and the building behind her was gone and she was falling backwards, splashing into a puddle. It took her a moment to figure it out.

"Fletcher!" she called. He didn't answer. She was sitting in a puddle in a filthy alleyway.

She didn't recognise her surroundings.

Skulduggery was gone.

She was alone.

She got up. It had to be Fletcher. He was the only Teleporter left alive. No one else could have done that. She took out her phone. Impossibly, it told her she didn't have a signal. But this phone always had a signal.

She walked out of the alley. The buildings were all old, old and dirty and small, made of brick and stone and wood. A man passed, dressed in dark brown, the colour of mud. A woman walked the other way, wearing the same colour. Valkyrie followed the woman to a wider street, but then stopped at the corner, hung back. Everyone here wore brown. Brown trousers, brown shirts, brown coats. They didn't wear it as a uniform, though it was just as if the only clothes available were all the same colour.

Valkyrie stepped into the street and suddenly people were turning around, changing direction, looking up at the sky or down at the road as they passed her. She started to feel very self-conscious dressed all in black. Two women approached, and Valkyrie walked over.

"Excuse me?"

They hurried by, heads down, pretending not to see her.

"Hey," she said. "Hey, hello. Excuse me."

"You should go."

She turned. A man in his forties, in those same brown clothes as everyone else. Balding and unshaven.

"Where am I?" she asked.

"Not where you're supposed to be," he said. "Do yourself a favour, do us all a favour, and leave. Please." He started walking. She followed.

"I don't know where I am. Tell me where I am."

"Pageant Street," he said brusquely.

"I mean what city."

"Dublin."

She frowned at him. "This isn't Dublin. I know Dublin, and this isn't..." A thought struck her. A horrible, amazing thought. "What year is this?"

"Year?"

It made sense. The old-style buildings. The fact that there were no cars, no technology. She'd travelled back in time. "Tell me what year this is."

He stopped suddenly and looked at her, fear in his eyes. "You're a sorcerer," he said.

Valkyrie blinked. "Uh..."

He backed away. "Oh, my... Oh, you're one of them. Please don't kill me. I only wanted to help. I didn't mean anything by it."

She followed, keeping her hands up, trying to calm him down. "You know about sorcerers?"

"I don't know anything, I swear. I'm no one."

She clapped her hands in front of his face and he jerked his head back. "Hey! Listen to me. I'm not going to hurt you. I just need to know some things. I'm not from here and I don't know how anything works. You say this is Dublin? What century?"

He looked at her like she was crazy. "Century? The twenty-first."

Oh. So she hadn't time-travelled. Fine. "What happened to it?" she asked next.

"What do you mean?"

"I mean what happened here? Where are the cars and the streetlights and how come everything is so old and dirty? Why is everyone wearing these clothes?"

"I don't want to get into any trouble."

"Answer my questions."

"But I don't know what you mean. It's always been like this."

"No," she said, "it hasn't. Dublin is brighter and bigger and flashier and... and OK, it's not a whole lot cleaner, but the people wear better clothes, that's for sure. I don't know what you're trying to pull but this isn't the Dublin that I know, all right? This..." And then it dawned on her. Nadir, the Dimensional Shunter. The throbbing in her arm. Whatever he'd done to her, this was the result. "I'm in a different reality," she said softly.

The balding man looked at her. "I'm sorry?"

"I'm not from this world," she told him. "You understand? I'm from one like it, but... different. We have cars and electricity and... Why is it like this? Why don't you have cars?"

"I don't know," the man said, distressed. "Is a car like a carriage? We have carriages. Horses pull them. I can show you where they're kept."

Valkyrie looked around. "Never mind. There are sorcerers here, right? Maybe they can help me."

The man paled. "You don't want to go to them."

"Why not?"

"If you don't know them, you don't want to know them. You should leave. Now. You should run."

A woman hurried by, waving a handkerchief by her side. The man turned.

"They're coming."

"Who are?" Valkyrie asked. "What's wrong?"

He took her hand, dragged her off the street. They ran between two buildings. He jumped a wall and she followed.

"What's going on?"

He didn't answer. He led her into a sagging house. The door was open and the floorboards were rotten. She followed him up the stairs and he crossed to the window.

"The Sense-Wardens are patrolling," he said. "Some of them can read your mind. When you see them, you have to just think of nothing, just focus on being empty, or they'll see something in your thoughts and they'll come for you. They got my wife, seven years ago. She didn't know they were there and they grabbed her off the street, took her away. I haven't seen her since."

"That's terrible."

"The ones in white," he said, "they're the Sense-Wardens."

Valkyrie joined him at the grime-covered window. Nine people passed below, three of whom wore white robes with hoods obscuring their faces. They walked slowly, hands clasped. Forming a circle around them were six people in robes of deep scarlet. Beneath the robes, black boots and loose garments. On their backs, scythes.

"They send the Redhoods after us," the man said bitterly. "There's no point in running. They're too fast. There's no point in fighting. They're too strong. And those blades of theirs... I once saw a man cut in two as easy as cutting paper."

"Cleavers," said Valkyrie. "They're called Cleavers. Or that's what they're called where I'm from. And they're dressed in grey, not red."

"Well, here they're called Redhoods," said the man, "and if one is coming for you, you surrender. Save yourself the pain."

He stepped away from the window but Valkyrie stayed where she was, watching. There was a symbol on the breast of their robes two circles, the smaller one barely bisecting the larger. She watched the Sense-Wardens and their guards move on, watched the people slow down to a stop as they approached. To suddenly turn and walk the other way would be a sign of something to hide, so instead the people paused, lowered their heads and closed their eyes. Probably focusing on being empty.

One of the Sense-Wardens turned his head, his hood shifting slightly. He stepped from the circle, slowly nearing a young woman with short cropped hair. Her eyes were closed but she could undoubtedly hear his footsteps. She stiffened, and even Valkyrie could see her face twitch with panic.

The Sense-Warden walked slowly round her. The young woman's shoulders started to shake. She was crying, but her eyes remained closed.

Another Sense-Warden broke from the circle, joining the first. A pale hand emerged from a voluminous sleeve and lightly touched the woman's head. She flinched and sobbed, and her legs gave out and she fell to her knees. She looked up at the Sense-Wardens as they backed away, and a Redhood came forward. He gripped the young woman's arm and pulled her to her feet.

"They have someone," Valkyrie said, her voice quiet. "A girl. Not much older than me."

The balding man, from somewhere behind her, spoke without emotion. "She'll be taken to the Palace. Whatever secrets she's hiding will come spilling out of her, and if they're bad enough, she'll be killed. If not, imprisonment."

"There must be someone who fights against this."

"There is," said the man. "At least, I think there is. For all I know it's just another legend, a story to tell our children at night. I wouldn't be surprised. Every sorcerer I've ever met has hated mortals. I suppose it's childish to think there are some out there who fight for us."

"I'm a sorcerer," said Valkyrie, "and I'll fight for you. For as long as I'm here, anyway."

The man shrugged. "Then by all means, go down there and save that girl."

She hesitated. "There are nine of them."

"And it's only one mortal girl," said the man, nodding. "She'd hardly be worth the risk."

Valkyrie glared at him. "That's not what I meant. I meant you've got to pick your battles. Charging in head first would only get me killed, and what use would I be to anyone then?"

"What use are you to anyone now?"

"I'm not going to die for someone I don't know in a reality I don't understand. This isn't even my dimension, for God's sake."

"Fair enough. No one could expect you to bother yourself."

"I wouldn't stand a chance anyway. If your Redhoods are the same as my Cleavers then their clothes are resistant to magic. I wouldn't last two seconds against nine of them." As she spoke, she looked out of the window. The Redhood was taking the young woman, who was now wearing shackles, back through the streets. The others, including the Sense-Wardens, had continued on in the other direction, out of sight. She looked at the Redhood and the young woman. "However..." she murmured.

"However what?"

"However, I might stand a chance against one of them."

She moved to the door but he stood in her way. "No."

Valkyrie arched an eyebrow. "No?"

"You can't."

"You were just saying-"

"Because I didn't think you'd try anything. If a Redhood is attacked, do you have any idea what that would mean? They'd tear through these streets looking for whoever did it. They'd torture and kill and take their anger out on innocent people. You can't interfere."

"But that girl-"

"Is one of a countless number who are taken off the streets every week. You can't save them all, and saving one would make it worse for everyone else."

"So no one does anything? How do you expect things to change if you're not willing to make a stand?"

The man laughed. "But I don't expect things to change. This is the way of the world. Those with magic rule and live for ever, and those without magic work and perish. You think it's any different in France? Britain? In what's left of America? Everywhere's the same." His voice softened. "Look, thank you for wanting to try. Even though I'm starting to doubt that you are a sorcerer and not just some lunatic, it's appreciated."

Valkyrie clicked her fingers and the balding man recoiled slightly from the fireball.

"OK," he said quickly, "you're a sorcerer."