CHAPTER ONE: What in the name of Zeus' beard is a muggle?

Percy didn't understand it. They'd just gone out for a movie, and now both Annabeth and Rachel were in tears.

"Um," Percy started, "What's wrong?"

Percy took a step back as Annabeth turned to face him. She was staring daggers with her bloodshot eyes.

"What's wrong?" she asked, her voice quivering, "What's WRONG?"

"Oh, absolutely nothing is wrong!" Rachel spit, "It's not like it's the end of the world or anything!"

"But," Percy said, "It isn't."

"ISN'T IT?" Annabeth yelled. Percy now wondered why he had bothered to open his mouth in the first place. He was even more confused than he was before.

"Come on," Rachel said, tugging at Annabeth's sleeve, "We should go see Chiron."

Whoa, whoa, whoa. Annabeth and Rachel weren't normally this friendly with each other. Unless …

"Wait, was there a prophecy?" Percy asked. He started to get concerned. "Is there something I need to know about?"

Both girls ignored him and kept walking towards the Big House. Percy followed.

"Guys, you're scaring me," Percy said, "What's going on?"

Silence again. They reached the door.

"So you're just gonna let me eavesdrop?" Percy said, trying to lighten the mood.

They walked in. "Chiron?" Rachel asked.

"I guess they are," Percy muttered to himself.

Chiron was slouched at the table, looking bereaved and grief-stricken. When he heard the three campers walk in, he sat up a little.

"You too?" he sighed. He slumped back in his wheelchair. "I'm sorry, I cannot help you this time."

"Chiron, it's too much," Annabeth said wearily, "I don't think some of the campers can survive much longer."

"It's just been there all these years," Rachel said, "Even for me. And suddenly, poof! It's gone."

"There's nothing left."

"Obliviated."

Annabeth looked at Rachel and burst into tears. Percy wasn't even sure that 'obliviated' was a word, but it didn't matter. Whatever was happening seemed to be having a serious effect on all of Annabeth, Rachel and Chiron. If only he knew what it was.

"Is there some kind of sickness spreading through camp?" Percy asked, "Some sort of disease?"

Everyone remained silent.

"How could I not have known about this?"

Again, no one answered. Chiron slumped even more into his wheelchair.

"Seriously people," Percy raised his voice, "What the hades is going on here?"

"Oh, shut up!" Annabeth screamed. Everyone else in the room flinched. "Shut UP! How would you know anything about it, you filthy muggle!"

What in the name of Zeus' beard was a muggle?

"What in the name of Zeus' beard is a muggle?" Percy asked.

Rachel's jaw dropped and Chiron got out of his wheelchair and stared.

"You mean," he said slowly, "You don't know?"

Percy shook his head. "Is it a monster? Or a swear word I've never heard about?"

Annabeth stormed out of the room. Percy watched as she left, befuddled as to what could possibly make her so angry. He hadn't seen her this mad since the last Titan war.

Chiron brought out seven books. Some were small, and others were ridiculously thick. Percy looked at the book resting on top of the stack. His dyslexia wouldn't let him read the title or the author, but on the cover was a picture of a boy in front of a train. As Chiron spread the books out, Percy recognised one of the books: it had a picture of a wizard on it.

"The security guard of the Empire State Building was reading that book," Percy remembered, "That was on my first trip to Olympus."

"Of course he was," Chiron nodded, "He always had a good taste in books. Except for that vampire series he used to be obsessed with …"

"Erk," Rachel gagged.

"Are they any good?" Percy asked.

"Terrible," Rachel screwed her nose up in distaste, "Sparkling vampires? Honestly?"

"I do not remember the empousai ever sparkling," Chiron admitted.

"No, no!" Percy said, "These books." He gestured to the ones spread out in front of him.

There was a moment of silence as Rachel's jaw dropped and Chiron sat back in his wheelchair with a thump.

"Is it any good, he asks," Rachel finally said.

Chiron hid his face in his hands. "Percy, are you trying to tell me that you have never heard of the Harry Potter series before?"

"Harry who?" Percy asked.

"Harry who." Rachel slapped her forehead with her palm.

"Harry Potter," Chiron said, with as much patience as he could muster.

Percy thought for a while. "Nope," he said, finally.

"Nope." Rachel raised her hands in exasperation.

"That's enough, Rachel," Chiron said. He crossed his fingers and rested his chin on his hands. "Perseus Jackson," Chiron said, "I did not realise how … ignorant you are."

"Ignorant?" Rachel cried, "He's been living under a rock!"

"Rachel, I said that's enough."

"Guys," Percy interrupted, "I don't see what the problem is. I mean, it's just a book, right?"

"Just a book?" Rachel yelled, "Just a BOOK?"

Percy took a step back. Rachel was really starting to sound like Annabeth, and that was not a good sign.

"Rachel," Chiron said quietly, "Perhaps you should organise a ride home. Relax a little. Calm down."

"Calm down," Rachel took a deep breath.

"Take a rest."

"Rest."

"Shed a few tears on your pillow."

"I wish I had a pillow right now."

"You could borrow my panda pillow pet if you like," Percy butt in, "As seen on TV."

The look Rachel gave him was so fierce that Percy had to take another step back. It was almost as if she was going to go all creepy green-eyed Oracle on him.

"Or not," Percy muttered quietly.

"Percy, in the nicest possible way, shut up," Chiron said. He turned to Rachel. "Use the phone. Call a cab."

Rachel nodded and glared at Percy one last time before walking out the door. Percy was starting to get seriously freaked out here. Rachel had just yelled at him and Chiron had told him to shut up. Things were supposed to be normal after the war.

Chiron buried his head in his hands. He stayed like that for a while. Percy didn't know what to say, so he remained silent. He didn't trust his mouth to say the right thing anyway. Everything he said today seemed to cause one outburst or another.

"I think I'll just go," Percy said, backing slowly out of the room.

"Wait," Chiron said. He stood up and gathered his seven books, putting them back where they came from. Percy stood awkwardly and waited for something to happen.

Chiron cocked his head and looked at Percy for a long time. Finally, he spoke: "Your timetable needs rescheduling."

"What?" Percy wondered what that had to do with anything.

"I think your sword-fighting is good enough," Chiron mused, "And all your water activities need to be replaced as well."

"Why?" Percy cried. He loved his lessons in the lake.

Chiron furrowed his brow. "Alright, I suppose you can keep canoeing. But your free-time needs to be omitted."

"You can't do that!"

"You'll also have to be excused from roster duty, I suppose."

"Wait a minute," Percy scratched his head, "What's the point of all this?"

Chiron stared at Percy for an entire minute. "You have a new class now, Percy. Harry Potter 101."