“Bring it in?” one asked.

“Yeah,” another said. “Movie’s just about done.”

I panicked. I didn’t have time to back up. There was nowhere to hide except…the cart. I scrambled inside and pulled the tarp over me, hoping no one had seen me. I curled my fingers around Riptide, just in case I had to fight.

The cart lurched forward.

“Oi,” a gruff voice said. “Thing weighs a ton.”

“It’s celestial bronze,” the other said. “What did you expect?”

I got pulled along. We turned a corner, and from the sound of the wheels echoing against the walls I guessed we had passed down a tunnel and into a smaller room. Hopefully I was not about to be dumped into a smelting pot. If they started to tip me over, I’d have to fight my way out quick. I heard lots of talking, chattering voices that didn’t sound human—somewhere between a seal’s bark and a dog’s growl. There were other sounds too—like an old-fashioned film projector and a tinny voice narrating.

“Just set it in the back,” a new voice ordered from across the room. “Now, younglings, please attend to the film. There will be time for questions afterward.”

The voices quieted down, and I could hear the film.

As a young sea demon matures, the narrator said, changes happen in the monster’s body. You may notice your fangs getting longer and you may have a sudden desire to devour human beings. These changes are perfectly normal and happen to all young monsters.

Excited snarling filled the room. The teacher—I guess it must have been a teacher—told the younglings to be quiet, and the film continued. I didn’t understand most of it, and I didn’t dare look. The film kept talking about growth spurts and acne problems caused by working in the forges, and proper flipper hygiene, and finally it was over.

“Now, younglings,” the instructor said, “what is the proper name of our kind?”

“Sea demons!” one of them barked.

“No. Anyone else?”

“Telekhines!” another monster growled.

“Very good,” the instructor said. “And why are we here?”

“Revenge!” several shouted.

“Yes, yes, but why?”

“Zeus is evil!” one monster said. “He cast us into Tartarus just because we used magic!”

“Indeed,” the instructor said. “After we made so many of the gods’ finest weapons. The trident of Poseidon, for one. And of course—we made the greatest weapon of the Titans! Nevertheless, Zeus cast us away and relied on those fumbling Cyclopes. That is why we are taking over the forges of the usurper Hephaestus. And soon we will control the undersea furnaces, our ancestral home!”

I clutched my pen-sword. These snarling things had created Poseidon’s trident? What were they talking about? I’d never even heard of a telekhine.

“And so, younglings,” the instructor continued, “who do we serve?”

“Kronos!” they shouted.

“And when you grow to be big telekhines, will you make weapons for the army?”

“Yes!”

“Excellent. Now, we’ve brought in some scraps for you to practice with. Let’s see how ingenious you are.”

There was a rush of movement and excited voices coming toward the cart. I got ready to uncap Riptide. The tarp was thrown back. I jumped up, my bronze sword springing to life in my hands, and found myself facing a bunch of…dogs.

Well, their faces were dogs, anyway, with black snouts, brown eyes, and pointy ears. Their bodies were sleek and black like sea mammals, with stubby legs that were half flipper, half foot, and humanlike hands with sharp claws. If you blended together a kid, a Doberman pinscher, and a sea lion, you’d get something like what I was looking at.

“A demigod!” one snarled.

“Eat it!” yelled another.

But that’s as far as they got before I slashed a wide arc with Riptide and vaporized the entire front row of monsters.

“Back off!” I yelled at the rest, trying to sound fierce. Behind them stood their instructor—a six-foot-tall telekhine with Doberman fangs snarling at me. I did my best to stare him down.

“New lesson, class,” I announced. “Most monsters will vaporize when sliced with a celestial bronze sword. This change is perfectly normal, and will happen to you right now if you don’t BACK OFF!”

To my surprise, it worked. The monsters backed up, but there were at least twenty of them. My fear factor wasn’t going to last long.

I jumped out of the cart, yelled, “CLASS DISMISSED!” and ran for the exit.

The monsters charged after me, barking and growling. I hoped they couldn’t run very fast with those stubby little legs and flippers, but they waddled along pretty well. Thank the gods there was a door in the tunnel leading out to the main cavern. I slammed it shut and turned the wheel handle to lock it, but I doubted it would keep them long.

I didn’t know what to do. Annabeth was out here somewhere, invisible. Our chance for a subtle reconnaissance mission had been blown. I ran toward the platform at the center of the lava lake.

***

“Annabeth!” I yelled.

“Shhh!” an invisible hand clamped over my mouth and wrestled me down behind a big bronze cauldron. “You want to get us killed?”

I found her head and took off her Yankees cap. She shimmered into existence in front of me, scowling, her face streaked with ash and grime. “Percy, what is your problem?”

“We’re going to have company!” I explained quickly about the monster orientation class. Her eyes widened.

“So that’s what they are,” she said. “Telekhines. I should’ve known. And they’re making…Well, look.”

We peeked over the cauldron. In the center of the platform stood four sea demons, but these were fully grown, at least eight feet tall. Their black skin glistened in the firelight as they worked, sparks flying as they took turns hammering on a long piece of glowing hot metal.

“The blade is almost complete,” one said. “It needs another cooling in blood to fuse the metals.”

“Aye,” a second said. “It shall be even sharper than before.”

“What is that?” I whispered.

Annabeth shook her head. “They keep talking about fusing metals. I wonder—”

“They were talking about the greatest Titan weapon,” I said. “And they…they said they made my father’s trident.”

“The telekhines betrayed the gods,” Annabeth said. “They were practicing dark magic. I don’t know what, exactly, but Zeus banished them to Tartarus.”

“With Kronos.”

She nodded. “We have to get out—”

No sooner had she said that than the door to the classroom exploded and young telekhines came pouring out. They stumbled over each other, trying to figure out which way to charge.

“Put your cap back on,” I said. “Get out!”

“What?” Annabeth shrieked. “No! I’m not leaving you.”

“I’ve got a plan. I’ll distract them. You can use the metal spider—maybe it’ll lead you back to Hephaestus. You have to tell him what’s going on.”

“But you’ll be killed!”

“I’ll be fine. Besides, we’ve got no choice.”

Annabeth glared at me like she was going to punch me. And then she did something that surprised me even more. She kissed me.

“Be careful, Seaweed Brain.” She put on her hat and vanished.

I probably would’ve sat there for the rest of the day, staring at the lava and trying to remember what my name was, but the sea demons jarred me back to reality.

“There!” one yelled. The entire class of telekhines charged across the bridge toward me. I ran for the middle of the platform, surprising the four elder sea demons so much they dropped the red-hot blade. It was about six feet long and curved like a crescent moon. I’d seen a lot of terrifying things, but this unfinished whatever-it-was scared me worse.

The elder demons got over their surprise quickly. There were four ramps leading off the platform, and before I could dash in any direction, each of them had covered an exit.

The tallest one snarled. “What do we have here? A son of Poseidon?”

“Yes,” another growled. “I can smell the sea in his blood.”

I raised Riptide. My heart was pounding.

“Strike down one of us, demigod,” the third demon said, “and the rest of us shall tear you to shreds. Your father betrayed us. He took our gift and said nothing as we were cast into the pit. We will see him sliced to pieces. He and all the other Olympians.”

I wished I had a plan. I wished I hadn’t been lying to Annabeth. I’d wanted her to get out safely, and I hoped she’d been sensible enough to do it. But now it was dawning on me that this might be the place I would die. No prophecies for me. I would get overrun in the heart of a volcano by a pack of dog-faced sea-lion people. The young telekhines were at the platform now, too, snarling and waiting to see how their four elders would deal with me.

I felt something burning against the side of my leg. The ice whistle in my pocket was getting colder. If I ever needed help, now was the time. But I hesitated. I didn’t trust Quintus’s gift.

Before I could make up my mind, the tallest telekhine said, “Let us see how strong he is. Let us see how long it takes him to burn!”

He scooped some lava out of the nearest furnace. It set his fingers ablaze, but this didn’t seem to bother him at all. The other elder telekhines did the same. The first one threw a glop of molten rock at me and set my pants on fire. Two more splattered across my chest. I dropped my sword in sheer terror and swatted at my clothes. Fire was engulfing me. Strangely, it felt only warm at first, but it was getting hotter by the instant.

“Your father’s nature protects you,” one said. “Makes you hard to burn. But not impossible, youngling. Not impossible.”

They threw more lava at me, and I remember screaming. My whole body was on fire. The pain was worse than anything I’d ever felt. I was being consumed. I crumpled to the metal floor and heard the sea demon children howling in delight.

Then I remembered the voice of the river naiad at the ranch: The water is within me.

I needed the sea. I felt a tugging sensation in my gut, but I had nothing around to help me. Not a faucet or a river. Not even a petrified seashell this time. And besides, the last time I’d unleashed my power at the stables, there’d been that scary moment when it had almost gotten away from me.

I had no choice. I called to the sea. I reached inside myself and remembered the waves and the currents, the endless power of the ocean. And I let it loose in one horrible scream.

Afterward, I could never describe what happened. An explosion, a tidal wave, a whirlwind of power simultaneously catching me up and blasting me downward into the lava. Fire and water collided, superheated steam, and I shot upward from the heart of the volcano in a huge explosion, just one piece of flotsam thrown free by a million pounds of pressure. The last thing I remember before losing conscious was flying, flying so high Zeus would never have forgiven me, and then beginning to fall, smoke and fire and water streaming from me. I was a comet hurtling toward the earth.