“Not even close. We’ve got a long way to go.”

“Whatever this mystery monster is, the General said it would come for you. They wanted to isolate you from the group, so the monster will appear and battle you one-on-one.”

“He said that?”

“Well, something like that. Yeah.”

“That’s great. I love being used as bait.”

“No idea what the monster might be?”

She shook her head morosely. “But you know where we’re going, don’t you? San Francisco. That’s where Artemis was heading.”

I remembered something Annabeth had said at the dance: how her dad was moving to San Francisco, and there was no way she could go. Half-bloods couldn’t live there.

“Why?” I asked. “What’s so bad about San Francisco?”

“The Mist is really thick there because the Mountain of Despair is so near. Titan magic—what’s left of it—still lingers. Monsters are attracted to that area like you wouldn’t believe.”

“What’s the Mountain of Despair?”

Thalia raised an eyebrow. “You really don’t know? Ask stupid Zoë. She’s the expert.”

She glared out the windshield. I wanted to ask her what she was talking about, but I also didn’t want to sound like an idiot. I hated feeling like Thalia knew more than I did, so I kept my mouth shut.

The afternoon sun shone through the steel-mesh side of the freight car, casting a shadow across Thalia’s face. I thought about how different she was from Zoë—Zoë all formal and aloof like a princess, Thalia with her ratty clothes and her rebel attitude. But there was something similar about them, too. The same kind of toughness. Right now, sitting in the shadows with a gloomy expression, Thalia looked a lot like one of the Hunters.

Then suddenly, it hit me: “That’s why you don’t get along with Zoë.”

Thalia frowned. “What?”

“The Hunters tried to recruit you,” I guessed.

Her eyes got dangerously bright. I thought she was going to zap me out of the Mercedes, but she just sighed.

“I almost joined them,” she admitted. “Luke, Annabeth, and I ran into them once, and Zoë tried to convince me. She almost did, but . . .”

“But?”

Thalia’s fingers gripped the wheel. “I would’ve had to leave Luke.”

“Oh.”

“Zoë and I got into a fight. She told me I was being stupid. She said I’d regret my choice. She said Luke would let me down someday.”

I watched the sun through the metal curtain. We seemed to be traveling faster each second—shadows flickering like an old movie projector.

“That’s harsh,” I said. “Hard to admit Zoë was right.”

“She wasn’t right! Luke never let me down. Never.”

“We’ll have to fight him,” I said. “There’s no way around it.”

Thalia didn’t answer.

“You haven’t seen him lately,” I warned. “I know it’s hard to believe, but—”

“I’ll do what I have to.”

“Even if that means killing him?”

“Do me a favor,” she said. “Get out of my car.”

I felt so bad for her I didn’t argue.

As I was about to leave, she said, “Percy.”

When I looked back, her eyes were red, but I couldn’t tell if it was from anger or sadness. “Annabeth wanted to join the Hunters, too. Maybe you should think about why.”

Before I could respond, she raised the power windows and shut me out.

* * *

I sat in the driver’s seat of Grover’s Lamborghini. Grover was asleep in the back. He’d finally given up trying to impress Zoë and Bianca with his pipe music after he played “Poison Ivy” and caused that very stuff to sprout from their Lexus’s air conditioner.

As I watched the sun go down, I thought of Annabeth. I was afraid to go to sleep. I was worried what I might dream.

“Oh, don’t be afraid of dreams,” a voice said right next to me.

I looked over. Somehow, I wasn’t surprised to find the homeless guy from the rail yard sitting in the shotgun seat. His jeans were so worn out they were almost white. His coat was ripped, with stuffing coming out. He looked kind of like a teddy bear that had been run over by a truck.

“If it weren’t for dreams,” he said, “I wouldn’t know half the things I know about the future. They’re better than Olympus tabloids.” He cleared his throat, then held up his hands dramatically:

“Dreams like a podcast,

Downloading truth in my ears.

They tell me cool stuff.”

“Apollo?” I guessed, because I figured nobody else could make a haiku that bad.

He put his finger to his lips. “I’m incognito. Call me Fred.”

“A god named Fred?”

“Eh, well . . . Zeus insists on certain rules. Hands off, when there’s a human quest. Even when something really major is wrong. But nobody messes with my baby sister. Nobody.”

“Can you help us, then?”

“Shhh. I already have. Haven’t you been looking outside?”

“The train. How fast are we moving?”

Apollo chuckled. “Fast enough. Unfortunately, we’re running out of time. It’s almost sunset. But I imagine we’ll get you across a good chunk of America, at least.”

“But where is Artemis?”

His face darkened. “I know a lot, and I see a lot. But even I don’t know that. She’s . . . clouded from me. I don’t like it.”

“And Annabeth?”

He frowned. “Oh, you mean that girl you lost? Hmm. I don’t know.”

I tried not to feel mad. I knew the gods had a hard time taking mortals seriously, even half-bloods. We lived such short lives, compared to the gods.

“What about the monster Artemis was seeking?” I asked. “Do you know what it is?”

“No,” Apollo said. “But there is one who might. If you haven’t yet found the monster when you reach San Francisco, seek out Nereus, the Old Man of the Sea. He has a long memory and a sharp eye. He has the gift of knowledge sometimes kept obscure from my Oracle.”

“But it’s your Oracle,” I protested. “Can’t you tell us what the prophecy means?”

Apollo sighed. “You might as well ask an artist to explain his art, or ask a poet to explain his poem. It defeats the purpose. The meaning is only clear through the search.”

“In other words, you don’t know.”

Apollo checked his watch. “Ah, look at the time! I have to run. I doubt I can risk helping you again, Percy, but remember what I said! Get some sleep! And when you return, I expect a good haiku about your journey!”

I wanted to protest that I wasn’t tired and I’d never made up a haiku in my life, but Apollo snapped his fingers, and the next thing I knew I was closing my eyes.

In my dream, I was somebody else. I was wearing an old-fashioned Greek tunic, which was a little too breezy downstairs, and laced leather sandals. The Nemean Lion’s skin was wrapped around my back like a cape, and I was running somewhere, being pulled along by a girl who was tightly gripping my hand.

“Hurry!” she said. It was too dark to see her face clearly, but I could hear the fear in her voice. “He will find us!”

It was nighttime. A million stars blazed above. We were running through tall grass, and the scent of a thousand different flowers made the air intoxicating. It was a beautiful garden, and yet the girl was leading me through it, as if we were about to die.

“I’m not afraid,” I tried to tell her.

“You should be!” she said, pulling me along. She had long dark hair braided down her back. Her silk robes glowed faintly in the starlight.

We raced up the side of the hill. She pulled me behind a thorn bush and we collapsed, both breathing heavily. I didn’t know why the girl was scared. The garden seemed so peaceful. And I felt strong. Stronger than I’d ever felt before.

“There is no need to run,” I told her. My voice sounded deeper, much more confident. “I have bested a thousand monsters with my bare hands.”

“Not this one,” the girl said. “Ladon is too strong. You must go around, up the mountain to my father. It is the only way.”

The hurt in her voice surprised me. She was really concerned, almost like she cared about me.