“This is only a taste of what is to come,” Luke said. “Soon we will be ready to storm Camp Half-Blood. And after that, Olympus itself. All we need is your help.”

For a terrible moment, Thalia hesitated. She gazed at Luke, her eyes full of pain, as if the only thing she wanted in the world was to believe him. Then she leveled her spear. “You aren’t Luke. I don’t know you anymore.”

“Yes, you do, Thalia,” he pleaded. “Please. Don’t make me . . . Don’t make him destroy you.”

There was no time. If that army got to the top of the hill, we would be overwhelmed. I met Annabeth’s eyes again. She nodded.

I looked at Thalia and Zoë, and I decided it wouldn’t be the worst thing in the world to die fighting with friends like this.

“Now,” I said.

Together, we charged.

Thalia went straight for Luke. The power of her shield was so great that his dragon-women bodyguards fled in a panic, dropping the golden coffin and leaving him alone. But despite his sickly appearance, Luke was still quick with his sword. He snarled like a wild animal and counterattacked. When his sword, Backbiter, met Thalia’s shield, a ball of lightning erupted between them, frying the air with yellow tendrils of power.

As for me, I did the stupidest thing in my life, which is saying a lot. I attacked the Titan Lord Atlas.

He laughed as I approached. A huge javelin appeared in his hands. His silk suit melted into full Greek battle armor. “Go on, then!”

“Percy!” Zoë said. “Beware!”

I knew what she was warning me about. Chiron had told me long ago: Immortals are constrained by ancient rules. But a hero can go anywhere, challenge anyone, as long as he has the nerve. Once I attacked, however, Atlas was free to attack back directly, with all his might.

I swung my sword, and Atlas knocked me aside with the shaft of his javelin. I flew through the air and slammed into a black wall. It wasn’t Mist anymore. The palace was rising, brick by brick. It was becoming real.

“Fool!” Atlas screamed gleefully, swatting aside one of Zoë’s arrows. “Did you think, simply because you could challenge that petty war god, that you could stand up to me?”

The mention of Ares sent a jolt through me. I shook off my daze and charged again. If I could get to that pool of water, I could double my strength.

The javelin’s point slashed toward me like a scythe. I raised Riptide, planning to cut off his weapon at the shaft, but my arm felt like lead. My sword suddenly weighed a ton.

And I remembered Ares’s warning, spoken on the beach in Los Angeles so long ago: When you need it most, your sword will fail you.

Not now! I pleaded. But it was no good. I tried to dodge, but the javelin caught me in the chest and sent me flying like a rag doll. I slammed into the ground, my head spinning. I looked up and found I was at the feet of Artemis, still straining under the weight of the sky.

“Run, boy,” she told me. “You must run!”

Atlas was taking his time coming toward me. My sword was gone. It had skittered away over the edge of the cliff. It might reappear in my pocket—maybe in a few seconds— but it didn’t matter. I’d be dead by then. Luke and Thalia were fighting like demons, lightning crackling around them. Annabeth was on the ground, desperately struggling to free her hands.

“Die, little hero,” Atlas said.

He raised his javelin to impale me.

“No!” Zoë yelled, and a volley of silver arrows sprouted from the armpit chink in Atlas’s armor.

“ARGH!” He bellowed and turned toward his daughter.

I reached down and felt Riptide back in my pocket. I couldn’t fight Atlas, even with a sword. And then a chill went down my back. I remembered the words of the prophecy: The Titan’s curse must one withstand. I couldn’t hope to beat Atlas. But there was someone else who might stand a chance.

“The sky,” I told the goddess. “Give it to me.”

“No, boy,” Artemis said. Her forehead was beaded with metallic sweat, like quicksilver. “You don’t know what you’re asking. It will crush you!”

“Annabeth took it!”

“She barely survived. She had the spirit of a true huntress. You will not last so long.”

“I’ll die anyway,” I said. “Give me the weight of the sky!”

I didn’t wait for her answer. I took out Riptide and slashed through her chains. Then I stepped next to her and braced myself on one knee—holding up my hands—and touched the cold, heavy clouds. For a moment, Artemis and I bore the weight together. It was the heaviest thing I’d ever felt, as if I were being crushed under a thousand trucks. I wanted to black out from the pain, but I breathed deeply. I can do this.

Then Artemis slipped out from under the burden, and I held it alone.

Afterward, I tried many times to explain what it felt like. I couldn’t.

Every muscle in my body turned to fire. My bones felt like they were melting. I wanted to scream, but I didn’t have the strength to open my mouth. I began to sink, lower and lower to the ground, the sky’s weight crushing me.

Fight back! Grover’s voice said inside my head. Don’t give up.

I concentrated on breathing. If I could just keep the sky aloft a few more seconds. I thought about Bianca, who had given her life so we could get here. If she could do that, I could hold the sky.

My vision turned fuzzy. Everything was tinged with red. I caught glimpses of the battle, but I wasn’t sure if I was seeing clearly. There was Atlas in full battle armor, jabbing with his javelin, laughing insanely as he fought. And Artemis, a blur of silver. She had two wicked hunting knives, each as long as her arm, and she slashed wildly at the Titan, dodging and leaping with unbelievable grace. She seemed to change form as she maneuvered. She was a tiger, a gazelle, a bear, a falcon. Or perhaps that was just my fevered brain. Zoë shot arrows at her father, aiming for the chinks in his armor. He roared in pain each time one found its mark, but they affected him like bee stings. He just got madder and kept fighting.

Thalia and Luke went spear on sword, lightning still flashing around them. Thalia pressed Luke back with the aura of her shield. Even he was not immune to it. He retreated, wincing and growling in frustration.

“Yield!” Thalia yelled. “You never could beat me, Luke.”

He bared his teeth. “We’ll see, my old friend.”

Sweat poured down my face. My hands were slippery. My shoulders would’ve screamed with agony if they could. I felt like the vertebrae in my spine were being welded together by a blowtorch.

Atlas advanced, pressing Artemis. She was fast, but his strength was unstoppable. His javelin slammed into the earth where Artemis had been a split second before, and a fissure opened in the rocks. He leaped over it and kept pursuing her. She was leading him back toward me.

Get ready, she spoke in my mind.

I was losing the ability to think through the pain. My response was something like Agggghh-owwwwwwww.

“You fight well for a girl.” Atlas laughed. “But you are no match for me.”

He feinted with the tip of his javelin and Artemis dodged. I saw the trick coming. Atlas’s javelin swept around and knocked Artemis’s legs off the ground. She fell, and Atlas brought up his javelin tip for the kill.

“No!” Zoë screamed. She leaped between her father and Artemis and shot an arrow straight into the Titan’s forehead, where it lodged like a unicorn’s horn. Atlas bellowed in rage. He swept aside his daughter with the back of his hand, sending her flying into the black rocks.

I wanted to shout her name, run to her aid, but I couldn’t speak or move. I couldn’t even see where Zoë had landed. Then Atlas turned on Artemis with a look of triumph in his face. Artemis seemed to be wounded. She didn’t get up.

“The first blood in a new war,” Atlas gloated. And he stabbed downward.