“That’s why you had trouble with the sun van.”

She gave me a wary look. “What do you mean?”

“The way you stiffened up. You must’ve been thinking about your mom, not wanting to get behind the wheel.”

I was sorry I’d said anything. Thalia’s expression was dangerously close to Zeus’s, the one time I’d seen him get angry— like any minute, her eyes would shoot a million volts.

“Yeah,” she muttered. “Yeah, that must’ve been it.”

She trudged off toward the court, where the Ares camper and the Hunter were trying to kill each other with a sword and a basketball.

The cabins were the weirdest collection of buildings you’ve ever seen. Zeus and Hera’s big white-columned buildings, Cabins One and Two, stood in the middle, with five gods’ cabins on the left and five goddesses’ cabins on the right, so they all made a U around the central green and the barbecue hearth.

I made the rounds, telling everybody about capture the flag. I woke up some Ares kid from his midday nap and he yelled at me to go away. When I asked him where Clarisse was he said, “Went on a quest for Chiron. Top secret!”

“Is she okay?”

“Haven’t heard from her in a month. She’s missing in action. Like your butt’s gonna be if you don’t get outta here!”

I decided to let him go back to sleep.

Finally I got to Cabin Three, the cabin of Poseidon. It was a low gray building hewn from sea stone, with shells and coral fossils imprinted in the rock. Inside, it was just as empty as always, except for my bunk. A Minotaur horn hung on the wall next to my pillow.

I took Annabeth’s baseball cap out of my backpack and set it on my nightstand. I’d give it to her when I found her. And I would find her.

I took off my wristwatch and activated the shield. It creaked noisily as it spiraled out. Dr. Thorn’s spikes had dented the brass in a dozen places. One gash kept the shield from opening all the way, so it looked like a pizza with two slices missing. The beautiful metal pictures that my brother had crafted were all banged up. In the picture of me and Annabeth fighting the Hydra, it looked like a meteor had made a crater in my head. I hung the shield on its hook, next to the Minotaur horn, but it was painful to look at now. Maybe Beckendorf from the Hephaestus cabin could fix it for me. He was the best armorsmith in the camp. I’d ask him at dinner.

I was staring at the shield when I noticed a strange sound—water gurgling—and I realized there was something new in the room. At the back of the cabin was a big basin of gray sea rock, with a spout like the head of a fish carved in stone. Out of its mouth burst a stream of water, a saltwater spring that trickled into the pool. The water must’ve been hot, because it sent mist into the cold winter air like a sauna. It made the room feel warm and summery, fresh with the smell of the sea.

I stepped up to the pool. There was no note attached or anything, but I knew it could only be a gift from Poseidon.

I looked into the water and said, “Thanks, Dad.”

The surface rippled. At the bottom of the pool, coins shimmered—a dozen or so golden drachma. I realized what the fountain was for. It was a reminder to keep in touch with my family.

I opened the nearest window, and the wintry sunlight made a rainbow in the mist. Then I fished a coin out of the hot water.

“Iris, O Goddess of the Rainbow,” I said, “accept my offering.”

I tossed a coin into the mist and it disappeared. Then I realized I didn’t know who to contact first.

My mom? That would’ve been the “good son” thing to do, but she wouldn’t be worried about me yet. She was used to me disappearing for days or weeks at a time.

My father? It had been way too long, almost two years, since I’d actually talked to him. But could you even send an Iris-message to a god? I’d never tried. Would it make them mad, like a sales call or something?

I hesitated. Then I made up my mind.

“Show me Tyson,” I requested. “At the forges of the Cyclopes.”

The mist shimmered, and the image of my half brother appeared. He was surrounded in fire, which would’ve been a problem if he weren’t a Cyclops. He was bent over an anvil, hammering a red-hot sword blade. Sparks flew and flames swirled around his body. There was a marble-framed window behind him, and it looked out onto dark blue water— the bottom of the ocean.

“Tyson!” I yelled.

He didn’t hear me at first because of the hammering and the roar of the flames.

“TYSON!”

He turned, and his one enormous eye widened. His face broke into a crooked yellow grin. “Percy!”

He dropped the sword blade and ran at me, trying to give me a hug. The vision blurred and I instinctively lurched back. “Tyson, it’s an Iris-message. I’m not really here.”

“Oh.” He came back into view, looking embarrassed. “Oh, I knew that. Yes.”

“How are you?” I asked. “How’s the job?”

His eye lit up. “Love the job! Look!” He picked up the hot sword blade with his bare hands. “I made this!”

“That’s really cool.”

“I wrote my name on it. Right there.”

“Awesome. Listen, do you talk to Dad much?”

Tyson’s smile faded. “Not much. Daddy is busy. He is worried about the war.”

“What do you mean?”

Tyson sighed. He stuck the sword blade out the window, where it made a cloud of boiling bubbles. When Tyson brought it back in, the metal was cool. “Old sea spirits making trouble. Aigaios. Oceanus. Those guys.”

I sort of knew what he was talking about. He meant the immortals who ruled the oceans back in the days of the Titans. Before the Olympians took over. The fact that they were back now, with the Titan Lord Kronos and his allies gaining strength, was not good.

“Is there anything I can do?” I asked.

Tyson shook his head sadly. “We are arming the mermaids. They need a thousand more swords by tomorrow.” He looked at his sword blade and sighed. “Old spirits are protecting the bad boat.”

“The Princess Andromeda?” I said. “Luke’s boat?”

“Yes. They make it hard to find. Protect it from Daddy’s storms. Otherwise he would smash it.”

“Smashing it would be good.”

Tyson perked up, as if he’d just had another thought. “Annabeth! Is she there?”

“Oh, well . . .” My heart felt like a bowling ball. Tyson thought Annabeth was just about the coolest thing since peanut butter (and he seriously loved peanut butter). I didn’t have the heart to tell him she was missing. He’d start crying so bad he’d probably put out his fires. “Well, no . . . she’s not here right now.”

“Tell her hello!” He beamed. “Hello to Annabeth!”

“Okay.” I fought back a lump in my throat. “I’ll do that.”

“And, Percy, don’t worry about the bad boat. It is going away.”

“What do you mean?”

“Panama Canal! Very far away.”

I frowned. Why would Luke take his demon-infested cruise ship all the way down there? The last time we’d seen him, he’d been cruising along the East Coast, recruiting half-bloods and training his monstrous army.

“All right,” I said, not feeling reassured. “That’s . . . good. I guess.”

In the forges, a deep voice bellowed something I couldn’t make out. Tyson flinched. “Got to get back to work! Boss will get mad. Good luck, Brother!”

“Ok, tell Dad—”

But before I could finish, the vision shimmered and faded. I was alone again in my cabin, feeling even lonelier than before.

* * *

I was pretty miserable at dinner that night.

I mean, the food was excellent as usual. You can’t go wrong with barbecue, pizza, and never-empty soda goblets. The torches and braziers kept the outdoor pavilion warm, but we all had to sit with our cabin mates, which meant I was alone at the Poseidon table. Thalia sat alone at the Zeus table, but we couldn’t sit together. Camp rules. At least the Hephaestus, Ares, and Hermes cabins had a few people each. Nico sat with the Stoll brothers, since new campers always got stuck in the Hermes cabin if their Olympian parent was unknown. The Stoll brothers seemed to be trying to convince Nico that poker was a much better game than Mythomagic. I hoped Nico didn’t have any money to lose.