"But… Oh, right. Yes, sir."

"Orientation film?" Nico asked. "Is it G or PG? 'Cause Bianca is kinda strict—"

"It's PG-13," Grover said.

"Cool!" Nico happily followed him out of the room.

"Now," Chiron said to Thalia and me, "perhaps you two should sit down and tell us the whole story."

When we were done, Chiron turned to Mr. D. "We should launch a search for Annabeth immediately."

"I'll go," Thalia and I said at the same time.

Mr. D sniffed. "Certainly not!"

Thalia and I both started complaining, but Mr. D held up his hand. He had that purplish angry fire in his eyes that usually meant something bad and godly was going to happen if we didn't shut up.

"From what you have told me," Mr. D said, "we have broken even on this escapade. We have, ah, regrettably lost Annie Bell—"

"Annabeth," I snapped. She'd gone to camp since she was seven, and still Mr. D pretended not to know her name.

"Yes, yes," he said. "And you procured a small annoying boy to replace her. So I see no point risking further half-bloods on a ridiculous rescue. The possibility is very great that this Annie girl is dead."

I wanted to strangle Mr. D. It wasn't fair Zeus had sent him here to dry out as camp director for a hundred years. It was meant to be a punishment for Mr. D's bad behavior on Olympus, but it ended up being a punishment for all of us.

"Annabeth may be alive," Chiron said, but I could tell he was having trouble sounding upbeat. He'd practically raised Annabeth all those years she was a year-round camper, before she'd given living with her dad and stepmom a second try. "She's very bright. If… if our enemies have her, she will try to play for time. She may even pretend to cooperate."

"That's right," Thalia said. "Luke would want her alive."

"In which case" said Mr. D, "I'm afraid she will have to be smart enough to escape on her own."

I got up from the table.

"Percy." Chiron's tone was full of warning. In the back of my mind, I knew Mr. D was not somebody to mess with. Even if you were an impulsive ADHD kid like me, he wouldn't give you any slack. But I was so angry I didn't care.

"You're glad to lose another camper," I said. "You'd like it if we all disappeared!"

Mr. D stifled a yawn. "You have a point?"

"Yeah," I growled. "Just because you were sent here as a punishment doesn't mean you have to be a lazy jerk! This is your civilization, too. Maybe you could try helping out a little!"

For a second, there was no sound except the crackle of the fire. The light reflected in Mr. D's eyes, giving him a sinister look. He opened his mouth to say something—probably a curse that would blast me to smithereens—when Nico burst into the room, followed by Grover.

"SO COOL!" Nico yelled, holding his hands out to Chiron. "You're… you're a centaur!"

Chiron managed a nervous smile. "Yes, Mr. di Angelo, if you please. Though, I prefer to stay in human form in this wheelchair for, ah, first encounters."

"And, whoa!" He looked at Mr. D. "You're the wine dude? No way!"

Mr. D turned his eyes away from me and gave Nico a look of loathing. "The wine dude?"

"Dionysus, right? Oh, wow! I've got your figurine."

"My figurine."

"In my game, Mythomagic. And a holofoil card, too! And even though you've only got like five hundred attack points and everybody thinks you're the lamest god card, I totally think your powers are sweet!"

"Ah." Mr. D seemed truly perplexed, which probably saved my life. "Well, that's… gratifying."

"Percy," Chiron said quickly, "you and Thalia go down to the cabins. Inform the campers we'll be playing capture the flag tomorrow evening."

"Capture the flag?" I asked. "But we don't have enough—"

"It is a tradition," Chiron said. "A friendly match, whenever the Hunters visit."

"Yeah," Thalia muttered. "I bet it's real friendly."

Chiron jerked his head toward Mr. D, who was still frowning as Nico talked about how many defense points all the gods had in his game. "Run along now," Chiron told us.

"Oh, right," Thalia said. "Come on, Percy."

She hauled me out of the Big House before Dionysus could remember that he wanted to kill me.

"You've already got Ares on your bad side," Thalia reminded me as we trudged toward the cabins. "You need another immortal enemy?"

She was right. My first summer as a camper, I'd gotten in a fight with Ares, and now he and all his children wanted to kill me. I didn't need to make Dionysus mad, too.

"Sorry," I said. "I couldn't help it. It's just so unfair."

She stopped by the armory and looked out across the valley, toward the top of Half-Blood Hill. Her pine tree was still there, the Golden Fleece glittering in its lowest branch. The tree's magic still protected the borders of camp, but it no longer used Thalia's spirit for power.

"Percy, everything is unfair," Thalia muttered. "Sometimes I wish…"

She didn't finish, but her tone was so sad I felt sorry for her. With her ragged black hair and her black punk clothes, an old wool overcoat wrapped around her, she looked like some kind of huge raven, completely out of place in the white landscape.

"We'll get Annabeth back," I promised. "I just don't know how yet."

"First I found out that Luke is lost," she said. "Now Annabeth—"

"Don't think like that."

"You're right." She straightened up. "We'll find a way."

Over at the basketball court, a few of the Hunters were shooting hoops. One of them was arguing with a guy from the Ares cabin. The Ares kid had his hand on his sword and the Hunter girl looked like she was going to exchange her basketball for a bow and arrow any second.

"I'll break that up," Thalia said. "You circulate around the cabins. Tell everybody about capture the flag tomorrow."

"All right. You should be team captain."

"No, no," she said. "You've been at camp longer. You do it."

"We can, uh… co-captain or something."

She looked about as comfortable with that as I felt, but she nodded.

As she headed for the court, I said, "Hey, Thalia."

"Yeah?"

"I'm sorry about what happened at Westover. I should've waited for you guys."

'"S okay, Percy. I probably would've done the same thing." She shifted from foot to foot, like she was trying to decide whether or not to say more. "You know, you asked about my mom and I kinda snapped at you. It's just… I went back to find her after seven years, and I found out she died in Los Angeles. She, um… she was a heavy drinker, and apparently she was out driving late one night about two years ago, and…" Thalia blinked hard.

"I'm sorry."

"Yeah, well. It's… it's not like we were ever close. I ran away when I was ten. Best two years of my life were when I was running around with Luke and Annabeth. But still—"

"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.