She looked at me gratefully, but then stared down at all the books and scrolls she’d pulled from the shelves. “I’m worried, Percy. Maybe I shouldn’t have asked you to do this. Or Tyson or Grover.”

“Hey, we’re your friends. We wouldn’t miss it.”

“But…” She stopped herself.

“What is it?” I asked. “The prophecy?”

“I’m sure it’s fine,” she said in a small voice.

“What was the last line?”

Then she did something that really surprised me. She blinked back tears and put out her arms.

I stepped forward and hugged her. Butterflies started turning my stomach into a mosh pit.

“Hey, it’s…it’s okay.” I patted her back.

I was aware of everything in the room. I felt like I could read the tiniest print on any book on the shelves. Annabeth’s hair smelled like lemon soap. She was shivering.

“Chiron might be right,” she muttered. “I’m breaking the rules. But I don’t know what else to do. I need you three. It just feels right.”

“Then don’t worry about it,” I managed. “We’ve had plenty of problems before, and we solved them.”

“This is different. I don’t want anything happening to…any of you.”

Behind me, somebody cleared his throat.

It was one of Annabeth’s half-brothers, Malcolm. His face was bright red. “Um, sorry,” he said. “Archery practice is starting, Annabeth. Chiron said to come find you.”

I stepped away from Annabeth. “We were just looking at maps,” I said stupidly.

Malcolm stared at me. “Okay.”

“Tell Chiron I’ll be right there,” Annabeth said, and Malcom left in a hurry.

Annabeth rubbed her eyes. “You go ahead, Percy. I’d better get ready for archery.”

I nodded, feeling more confused than I ever had in my life. I wanted to run from the cabin…but then again I didn’t.

“Annabeth?” I said. “About your prophecy. The line about a hero’s last breath—”

“You’re wondering which hero? I don’t know.”

“No. Something else. I was thinking the last line usually rhymes with the one before it. Was it something about—did it end in the word death?”

Annabeth stared down at her scrolls. “You’d better go, Percy. Get ready for the quest. I’ll—I’ll see you in the morning.”

I left her there, staring at maps that led from nowhere to nowhere; but I couldn’t shake the feeling that one of us wasn’t going to come back from this quest alive.

FIVE

NICO BUYS HAPPY MEALS FOR THE DEAD

At least I got a good night’s sleep before the quest, right?

Wrong.

That night in my dreams, I was in the stateroom of the Princess Andromeda. The windows were open on a moonlit sea. Cold wind rustled the velvet drapes.

Luke knelt on a Persian rug in front of the golden sarcophagus of Kronos. In the moonlight, Luke’s blond hair looked pure white. He wore an ancient Greek chiton and a white himation, a kind of cape that flowed down his shoulders. The white clothes made him look timeless and a little surreal, like one of the minor gods on Mount Olympus. The last time I’d seen him, he’d been broken and unconscious after a nasty fall from Mount Tam. Now he looked perfectly fine. Almost too healthy.

“Our spies report success, my lord,” he said. “Camp Half-Blood is sending a quest, as you predicted. Our side of the bargain is almost complete.”

Excellent. The voice of Kronos didn’t so much speak as pierce my mind like a dagger. It was freezing with cruelty. Once we have the means to navigate, I will lead the vanguard through myself.

Luke closed his eyes as if collecting his thoughts. “My lord, perhaps it is too soon. Perhaps Krios or Hyperion should lead—”

No. the voice was quiet but absolutely firm. I will lead. One more heart shall join our cause, and that will be sufficient. At last I shall rise fully from Tartarus.

“But the form, my lord…” Luke’s voice started shaking.

Show me your sword, Luke Castellan.

A jolt went through me. I realized I’d never heard Luke’s last name before. It had never even occurred to me.

Luke drew his sword. Backbiter’s double edge glowed wickedly—half steel, half celestial bronze. I’d almost been killed several times by that sword. It was an evil weapon, able to kill both mortals and monsters. It was the only blade I really feared.

You pledged yourself to me, Kronos reminded him. You took this sword as proof of your oath.

“Yes, my lord. It’s just—”

You wanted power. I gave you that. You are now beyond harm. Soon you will rule the world of gods and mortals. Do you not wish to avenge yourself? To see Olympus destroyed?

A shiver ran through Luke’s body. “Yes.”

The coffin glowed, golden light filling the room. Then make ready the strike force. As soon as the bargain is done, we shall move forward. First, Camp Half-Blood will be reduced to ashes. Once those bothersome heroes are eliminated, we will march on Olympus.

There was a knock on the stateroom doors. The light of the coffin faded. Luke rose. He sheathed his sword, adjusted his white clothes, and took a deep breath.

“Come in.”

The doors opened. Two dracaenae slithered in—snake women with double serpent trunks instead of legs. Between them walked Kelli, the empousa cheerleader from my freshman orientation.

“Hello, Luke,” Kelli smiled. She was wearing a red dress and she looked awesome, but I’d seen her real form. I knew what she was hiding: mismatched legs, red eyes, fangs, and flaming hair.

“What is it, demon?” Luke’s voice was cold. “I told you not to disturb me.”

Kelli pouted. “That’s not very nice. You look tense. How about a nice shoulder massage?”

Luke stepped back. “If you have something to report, say it. Otherwise leave!”

“I don’t know why you’re so huffy these days. You used to be fun to hang around.”

“That was before I saw what you did to that boy in Seattle.”

“Oh, he meant nothing to me,” Kelli said. “Just a snack, really. You know my heart belongs to you, Luke.”

“Thanks, but no thanks. Now report or get out.”

Kelli shrugged. “Fine. The advanced team is ready, as you surprised. We can leave—” She frowned.

“What is it?” Luke asked.

“A presence,” Kelli said. “Your senses are getting dull, Luke. We’re being watched.”

She scanned the stateroom. Her eyes focused right on me. Her face withered into a hag’s. She bared her fangs and lunged.

***

I woke with a start, my heart pounding. I could’ve sworn the empousa’s fangs were an inch from my throat.

Tyson was snoring in the next bunk. The sound calmed me down a little.

I didn’t know how Kelli could sense me in a dream, but I’d heard more than I wanted to know. An army was ready. Kronos would lead it personally. All they needed was a way to navigate the Labyrinth so they could invade and destroy Camp Half-Blood, and Luke apparently thought that was going to happen very soon.

I was tempted to go wake up Annabeth and tell her, middle of the night or not. Then I realized the room was lighter than it should have been. A blueand-green glow was coming from the saltwater fountain, brighter and more urgent than the night before. It was almost like the water was humming.

I got out of bed and approached.

No voice spoke out of the water this time, asking for a deposit. I got the feeling the fountain was waiting for me to make the first move.

I probably should’ve gone back to bed. Instead I thought about what I’d seen last night—the weird image of Nico at the banks of the River Styx.

“You’re trying to tell me something,” I said.

No response from the fountain.

“All right,” I said. “Show me Nico di Angelo.”

I didn’t even throw a coin in, but this time it didn’t matter. It was like some other force had control of the water besides Iris the messenger goddess. The water shimmered. Nico appeared, but he was no longer in the Underworld. He was standing in a graveyard under a starry sky. Giant willow trees loomed all around him.

He was watching some gravediggers at work. I heard shovels and saw dirt flying out of a hole. Nico was dressed in a black cloak. The night was foggy. It was warm and humid, and frogs were croaking. A large Wal-Mart bag sat next to Nico’s feet.

“Is it deep enough yet?” Nico asked. He sounded irritated.

“Nearly, my lord.” It was the same ghost I’d seen Nico with before, the faint shimmering image of a man. “But, my lord, I tell you, this is unnecessary. You already have me for advice.”

“I want a second opinion!” Nico snapped his fingers, and the digging stopped. Two figures climbed out of the hole. They weren’t people. They were skeletons in ragged clothes.

“You are dismissed,” Nico said. “Thank you.”

The skeletons collapsed into piles of bones.

“You might as well thank the shovels,” the ghost complained. “They have as much sense.”

Nico ignored him. He reached into his Wal-Mart bag and pulled out a twelve-pack of Coke. He popped open a can. Instead of drinking it, he poured it into the grave.

“Let the dead taste again,” he murmured. “Let them rise and take this offering. Let them remember.”

He dropped the rest of the Cokes into the grave and pulled out a white paper bag decorated with cartoons. I hadn’t seen one in years, but I recognized it—a McDonald’s Happy Meal.

He turned it upside down and shook the fries and hamburger into the grave.

“In my day, we used animal blood,” the ghost mumbled. “It’s perfectly good enough. They can’t taste the difference.”

“I will treat them with respect,” Nico said.

“At least let me keep the toy,” the ghost said.

“Be quiet!” Nico ordered. He emptied another twelve-pack of soda and three more Happy Meals into the grave, then began chanting in Ancient Greek. I caught only some of the words—a lot about the dead and memories and returning from the grave. Real happy stuff.

The grave started to bubble. Frothy brown liquid rose to the top like the whole thing was filling with soda. The fog thickened. The frogs stopped croaking. Dozens of figures began to appear among the gravestones: bluish, vaguely human shapes. Nico had summoned the dead with Coke and cheeseburgers.

“There are too many,” the ghost said nervously. “You don’t know your own powers.”

“I’ve got it under control,” Nico said, though his voice sounded fragile. He drew his sword—a short blade made of solid black metal. I’d never seen anything like it. It wasn’t celestial bronze or steel. Iron, maybe? The crowd of shades retreated at the sight of it.

“One at a time,” Nico commanded.

A single figure floated forward and knelt at the pool. It made slurping sounds as it drank. Its ghostly hands scooped French fries out of the pool.