“Yeah. I’m fine. I guess.”

“I heard stories,” Poseidon said. “But I wanted to hear it directly from you. Tell me everything.”

So I did. It was kind of disconcerting, because Poseidon listened so intently. His eyes never left my face. His expression didn’t change the whole time I talked. When I was done, he nodded slowly.

“So Kronos is indeed back. It will not be long before full war is upon us.”

“What about Luke?” I asked. “Is he really gone?”

“I don’t know, Percy. It is most disturbing.”

“But his body is mortal. Couldn’t you just destroy him?”

“Mortal, perhaps, but there is something different about Luke, my boy. I don’t know how he was prepared to host the Titan’s soul, but he will not be easily killed. And yet, I fear he must be killed if we are to send Kronos back to the pit. I will have to think on this. Unfortunately, I have other problems of my own.”

I remembered what Tyson had told me at the beginning of the summer. “The old sea gods?”

“Indeed. The battle came first to me, Percy. In fact, I cannot stay long. Even now the ocean is at war with itself. It is all I can do to keep hurricanes and typhoons from destroying your surface world, the fighting is so intense.”

“Let me come down there,” I said. “Let me help.”

Poseidon’s eyes crinkled as he smiled. “Not yet, my boy. I sense you will be needed here. Which reminds me…” He brought out a sand dollar and pressed it into my hand. “Your birthday present. Spend it wisely.”

“Uh, spend a sand dollar?”

“Oh, yes. In my day, you could buy quite a lot with a sand dollar. I think you will find it still buys a lot, if used in the right situation.”

“What situation?”

“When the time comes,” Poseidon said, “I think you’ll know.”

I closed my hand around the sand dollar, but something was really bothering me.

“Dad,” I said, “when I was in the maze, I met Antaeus. He said…well, he said he was your favorite son. He decorated his arena with skulls and—”

“He dedicated them to me,” Poseidon supplied. “And you are wondering how someone could do something so horrible in my name.”

I nodded uncomfortably.

Poseidon put his weathered hand on my shoulder. “Percy, lesser beings do many horrible things in the name of the gods. That does not mean we gods approve. The way our sons and daughters act in our names…well, it usually says more about them than it does about us. And you, Percy, are my favorite son.”

He smiled, and at that moment, just being in the kitchen with him was the best birthday present I ever got. Then my mom called from the living room. “Percy? The candles are melting!”

“You’d better go,” Poseidon said. “But, Percy, one last thing you should know. That incident at Mount St. Helens…”

For a second I thought he was talking about Annabeth kissing me, and I blushed, but then I realized he was talking about something a lot bigger.

“The eruptions are continuing,” he said. “Typhon is stirring. It is very likely that soon, in a few months, perhaps a year at best, he will escape his bonds.”

“I’m sorry,” I said. “I didn’t mean—”

Poseidon raised his hand. “It is not your fault, Percy. It would’ve happened sooner or later, with Kronos awakening the ancient monsters. But be aware, if Typhon stirs…it will be unlike anything you have faced before. The first time he appeared, all the forces of Olympus were barely enough to battle him. And when he stirs again, he will come here, to New York. He will make straight for Olympus.”

That was just the kind of wonderful news I wanted to get on my birthday, but Poseidon patted me on the back like everything was fine. “I should go. Enjoy your cake.”

And just like that he turned to mist and was swept out the window on a warm ocean breeze.

***

It took a little work to convince Paul that Poseidon had left via the fire escape, but since people can’t vanish into thin air, he had no choice but to believe it.

We ate blue cake and ice cream until we couldn’t eat anymore. Then we played a bunch of cheesy party games like charades and Monopoly. Tyson didn’t get charades. He kept shouting out the answer he was trying to mime, but it turned out he was really good at Monopoly. He knocked me out of the game in the first five rounds and started bankrupting my mom and Paul. I left them playing and went into my bedroom.

I set an uneaten slice of blue cake on my dresser. Then I took off my Camp Half-Blood necklace and laid it on the windowsill. There were three beads now, representing my three summers at camp—a trident, the Golden Fleece, and the latest: an intricate maze, symbolizing the Battle of the Labyrinth, as the campers had started to call it. I wondered what next year’s bead would be, if I was still around to get it. If the camp survived until next summer.

I looked at the phone by my bedside. I thought about calling Rachel Elizabeth Dare. My mom had asked me if there was anyone else I wanted to have over tonight, and I’d thought about Rachel. But I didn’t call. I don’t know why. The idea made me almost as nervous as a door into the Labyrinth.

I patted my pockets and emptied out my stuff—Riptide, a Kleenex, my apartment key. Then I patted my shirt pocket and felt a small lump. I hadn’t even realized it, but I was wearing the white cotton shirt Calypso had given me on Ogygia. I brought out a little piece of cloth, unwrapped it, and found the clipping of moonlace. It was a tiny sprig, shriveled up after two months, but I could still smell the faint scent of the enchanted garden. It made me sad.

I remembered Calypso’s last request of me: Plant a garden in Manhattan for me, will you? I opened the window and stepped onto the fire escape.

My mom kept a planter box out there. In the spring she usually filled it with flowers, but now it was all dirt, waiting for something new. It was a clear night. The moon was full over Eighty-second Street. I planted the dried sprig of moonlace carefully in the dirt and sprinkled a little nectar on it from my camp canteen.

Nothing happened at first.

Then, as I watched, a tiny silver plant sprang out of the soil—a baby moonlace, growing in the warm summer night.

“Nice plant,” a voice said.

I jumped. Nico di Angelo was standing on the fire escape right next to me. He’d just appeared there.

“Sorry,” he said. “Didn’t mean to startle you.”

“That’s—that’s okay. I mean…what are you doing here?”

He’d grown about an inch taller over the last couple of months. His hair was a shaggy black mess. He wore a black T-shirt, black jeans, and a new silver ring shaped like a skull. His Stygian iron sword hung at his side.

“I’ve done some exploring,” he said. “Thought you’d like to know, Daedalus got his punishment.”

“You saw him?”

Nico nodded. “Minos wanted to boil him in cheese fondue for an eternity, but my father had other ideas. Daedalus will be building overpasses and exit ramps in Asphodel for all time. It’ll help ease the traffic congestion. Truthfully, I think the old guy is pretty happy with that. He’s still building. Still creating. And he gets to see his son and Perdix on the weekends.”

“That’s good.”

Nico tapped at his silver ring. “But that’s not the real reason I’ve come. I’ve found out some things. I want to make you an offer.”

“What?”

“The way to beat Luke,” he said. “If I’m right, it’s the only way you’ll stand a chance.”

I took a deep breath. “Okay. I’m listening.”

Nico glanced inside my room. His eyebrows furrowed. “Is that…is that blue birthday cake?”

He sounded hungry, maybe a little wistful. I wondered if the poor kid had ever had a birthday party, or if he’d ever even been invited to one.

“Come inside for some cake and ice cream,” I said. “It sounds like we’ve got a lot to talk about.”