As they neared the end of the corridor, the new girl turned to him and smiled. “Adedayo, my name is Valkyrie Cain. I heard you had some interesting visitors last night.”

He stopped. “How did you know about that?”

Valkyrie took his arm, started him moving again. “I’ll explain everything later, I swear. Or maybe I won’t. It kinda depends on the threat level we’re facing, to be honest. But I’ll tell you what we know, OK? It won’t take long, because we don’t know a huge amount. Three creatures appeared in your house last night and then promptly left.”

She paused. “And that’s it. That’s as much as we know. Well, apart from the fact that these creatures – they’re pretty bad news. But I probably don’t have to tell you that. Do I? I probably don’t.”

“Who are you?”

“Like I said, my name’s Valkyrie Cain. I’m the good guy.”

They heard the door open behind them.

“We can run, if you like,” she said, smiling, and broke into a jog. Adedayo jogged alongside her round the next corner.

“Did they say anything, the creatures?” she asked. “Did they mention who they were, what they wanted, anything like that?”

“All they said was that my bedroom smelled of feet.”

“Huh,” Valkyrie said. “That’s a little mean, isn’t it? Even if your bedroom does smell of feet, they didn’t have to say it. Didn’t have to point it out. You know the problem with supernatural creatures? They’re rude. Yes, a lot of them also want to kill humans and/or destroy the world, but I’d say their main problem is the rudeness.”

“Where are we going?” Adedayo asked as they jogged past the balcony overlooking the sports hall.

“That way,” said Valkyrie, nodding to the exit at the bottom of the stairs.

He slowed. “What? I can’t leave school.”

“Of course you can. You do it every day.”

“But classes haven’t ended. I’ll get in trouble.”

Valkyrie put a hand on his shoulder and led him down the stairs. “I used to worry about things like that,” she said. “I used to worry about teachers and homework and detentions, and what other people thought of me, and what my friends said, and what to wear, and what music to listen to, and none of this is true. I didn’t worry about any of that because I’m way too cool and always have been, but at least I’ve managed to distract you long enough for us to get outside.”

She pushed open the doors and they emerged into the fresh air. Adedayo looked around, expecting a horde of teachers to come sprinting up. Instead, an empty crisp packet skipped lightly over the ground.

“Come along,” said Valkyrie, and strode across the courtyard. He didn’t know why, exactly, but he followed her. They passed the Old House, a tall, imposing building that used to be the main school a hundred years ago, but was now for staff only. They walked right by the window of the principal’s office. No one saw them.

There was a big black car parked in the staff car park – an old-fashioned car that gleamed in the sunlight. No one else was around.

“You’re a sorcerer, aren’t you?” Adedayo asked.

Valkyrie looked at him, surprised. “You know about us?”

“My ìyá agba – I mean, my gran – told me. She said I’m one of you.”

“Oh, thank God,” Valkyrie said, laughing. “I hate having to explain to mortals that magic and monsters exist and yes, there are bad guys, but we’re the good guys and please, please stop screaming. I hate when they scream, y’know? It’s just so unnecessary.”

“Totally,” said Adedayo.

A man got out of the car – a tall man in a dark blue suit, with a crisp white shirt and a dark blue tie. His hands were gloved and he wore a hat, like a detective in an old black-and-white movie.

“Adedayo,” said Valkyrie, “this is my partner, Skulduggery Pleasant.”

Adedayo was about to remark on such an unusual name when Skulduggery Pleasant tapped his shirt, just over the collarbones, and his face melted, actually melted, flowing off his bare bones and disappearing beneath his collar, so that what Adedayo saw looking at him now was just a skull wearing a hat.

“Hello, Adedayo,” the skeleton said, “very pleased to meet you.”

And Adedayo screamed.