Flamel sighed. “Dee is a necromancer. It is a foul and horrible art that involves artificially activating a dead body’s aura and bringing that body back to life.”

An icy coldness washed over Josh at the thought. “You’re saying he would have killed us and brought us back to life?”

“Yes. As a last resort.” Flamel reached out and squeezed the boy’s shoulder gently. “Believe me, it is a terrible existence, the merest shadow of life. And remember, Dee saw what you did, so he now has some inkling of your powers. If there were any doubts in his mind that you are the twins of legend, they have vanished. He has to have you. He needs you.” The Alchemyst poked Josh in the chest. Paper rustled. Beneath his T-shirt, in a cloth bag hanging around his neck, Josh carried the two pages he’d torn from the Codex. “And above all else, he needs those pages.”

The group followed the signs for the Euston Road exit, and were swept along by a crowd of commuters heading in the same direction. “I thought you said there would be someone to meet us,” Sophie said, looking around.

“Saint-Germain told me he’d try and contact an old friend,” Flamel muttered. “Maybe he couldn’t get in touch.”

They stepped out of the ornate redbrick train station onto Euston Road and stopped in surprise. When they’d left Paris just over two and a half hours ago, the skies had been cloudless, the temperature already creeping into the seventies, but in London it felt at least ten degrees cooler and it was raining hard. The wind whipping down the road was cold enough to make the twins shiver. They turned and ducked back into the shelter of the station.

And that was when Sophie saw him.

“A boy in a green parka, with the hood pulled up,” she said suddenly, turning to Nicholas and concentrating fiercely on his pale eyes. She knew that if she looked away, she would involuntarily glance at the young man who had been hurrying after them. She could still see him from the corner of her eye. He was loitering close to a pillar, staring at the cell phone in his hand, fiddling with it. There was something wrong about the way he was standing. Something unnatural. And she thought she caught the faintest scent of spoiled meat on the air. Her nose wrinkled. Closing her eyes, she concentrated on the odor. “It smells like something rotten, like roadkill.”

The smile on the Alchemyst’s face grew strained. “Wearing a hood? So, that’s who’s been following us.” The twins heard the slightest tremor in his voice.

“Except he’s not a boy, is he?” Sophie asked.

Nicholas shook his head. “Not even close.”