She turned toward her brother. Her expression was sad, as if she’d been dreading this moment. “Hello, Nico. You’ve gotten so tall.”

“Why didn’t you answer me sooner?” he cried. “I’ve been trying for months!”

“I was hoping you would give up.”

“Give up?” He sounded heartbroken. “How can you say that? I’m trying to save you!”

“You can’t, Nico. Don’t do this. Percy is right.”

“No! He let you die! He’s not your friend.”

Bianca stretched out a hand as if to touch her brother’s face, but she was made of mist. Her hand evaporated as it got close to living skin.

“You must listen to me,” she said. “Holding a grudge is dangerous for a child of Hades. It is our fatal flaw. You have to forgive. You have to promise me this.”

“I can’t. Never.”

“Percy has been worried about you, Nico. He can help. I let him see what you were up to, hoping he would find you.”

“So it was you,” I said. “You sent those Iris-messages.”

Bianca nodded.

“Why are you helping him and not me?” Nico screamed. “It’s not fair!”

“You are close to the truth now,” Bianca told him. “It’s not Percy you’re mad at, Nico. It’s me.”

“No.”

“You’re mad because I left you to become a Hunter of Artemis. You’re mad because I died and left you alone. I’m sorry for that, Nico. I truly am. But you must overcome the anger. And stop blaming Percy for my choices. It will be your doom.”

“She’s right,” Annabeth broke in. “Kronos is rising, Nico. He’ll twist anyone he can to his cause.”

“I don’t care about Kronos,” Nico said. “I just want my sister back.”

“You can’t have that, Nico,” Bianca told him gently.

“I’m the son of Hades! I can.”

“Don’t try,” she said. “If you love me, don’t…”

Her voice trailed off. Spirits had started to gather around us again, and they seemed agitated. Their shadows shifted. Their voices whispered,

Danger!

“Tartarus stirs,” Bianca said. “Your power draws the attention of Kronos. The dead must return to the Underworld. It is not safe for us to remain.”

“Wait,” Nico said. “Please—”

“Good-bye, Nico,” Bianca said. “I love you. Remember what I said.”

Her form shivered and the ghosts disappeared, leaving us alone with a pit, a Happy Flush septic tank, and a cold full moon.

***

None of us were anxious to travel that night, so we decided to wait until morning. Grover and I crashed on the leather couches in Geryon’s living room, which was a lot more comfortable than a bedroll in the maze; but it didn’t make my nightmares any better.

I dreamed I was with Luke, walking through the dark palace on top of Mount Tam. It was a real building now—not some half-finished illusion like I’d seen last winter. Green fires burned in braziers along the walls. The floor was polished black marble. A cold wind blew down the hallway, and above us through the open ceiling, the sky swirled with gray storm clouds.

Luke was dressed for battle. He wore camouflage pants, a white T-shirt, and a bronze breastplate, but his sword, Backbiter, wasn’t at his side—only and empty scabbard. We walked into a large courtyard where dozens of warriors and dracaenae were preparing for war. When they saw him, the demigods rose to attention. They beat their swords against their shields.

“Issss it time, my lord?” a dracaena asked.

“Soon,” Luke promised. “Continue your work.”

“My lord,” a voice said behind him. Kelli the empousa was smiling at him. She wore a blue dress tonight, and looked wickedly beautiful. Her eyes flickered—sometimes dark brown, sometimes pure red. Her hair was braided down her back and seemed to catch the light of the torches, as if it were anxious to turn back into pure flame.

My heart was pounding. I waited for Kelli to see me, to chase me out of the dream as she did before, but this time she didn’t seem to notice me.

“You have a visitor,” she told Luke. She stepped aside, and even Luke seemed stunned by what he saw.

The monster Kampê towered above him. Her snakes hissed around her legs. Animal heads growled at her waist. Her swords were drawn, shimmering with poison, and with her bat wings extended, she took up the entire corridor.

“You.” Luke’s voice sounded a little shaky. “I told you to stay on Alcatraz.”

Kampê’s eyelids blinked sideways like a reptile’s. she spoke in that weird rumbling language, but this time I understood, somewhere in the back of my mind: I come to serve. Give me revenge.

“You’re a jailor,” Luke said. “Your job—”

I will have them dead. No one escapes me.

Luke hesitated. A line of sweat trickled down the side of his face. “Very well,” he said. “You will go with us. You may carry Ariadne’s string. It is a position of great honor.”

Kampê hissed at the stars. She sheathed her swords and turned, pounding down the hallway on her enormous dragon legs.

“We should have left that one in Tartarus,” Luke mumbled. “She is too chaotic. Too powerful.”

Kelli laughed softly. “You should not fear power, Luke. Use it!”

“The sooner we leave, the better,” Luke said. “I want this over with.”

“Aww,” Kelli sympathized, running a finger down his arm. “You find it unpleasant to destroy your old camp?”

“I didn’t say that.”

“You’re not having second thoughts about your own, ah, special part?”

Luke’s face turned stony. “I know my duty.”

“That is good,” the demon said. “Is our strike force sufficient, do you think? Or will I need to call Mother Hecate for help?”

“We have more than enough,” Luke said grimly. “The deal is almost complete. All I need now is to negotiate safe passage through the arena.”

“Mmm,” Kelli said. “That should be interesting. I would hate to see your handsome head on a spike if you fail.”

“I will not fail. And you, demon, don’t you have other matters to attend to?”

“Oh, yes.” Kelli smiled. “I am bringing despair to your eavesdropping enemies. I am doing that right now.”

She turned her eyes directly on me, exposed her talons, and ripped through my dream.

Suddenly I was in a different place.

I stood at the top of a stone tower, overlooking rocky cliffs and the ocean below. The old man Daedalus was hunched over a worktable, wrestling with some kind of navigational instrument, like a huge compass. He looked years older than when I’d last seen him. He was stooped and his hands were gnarled. He cursed in Ancient Greek and squinted as if he couldn’t see his work, even though it was a sunny day.

“Uncle!” a voice called.

A smiling boy about Nico’s age came bounding up the steps, carrying a wooden box.

“Hello, Perdix,” the old man said, though his tone sounded cold. “Done with your projects already?”

“Yes, Uncle. They were easy!”

Daedalus scowled. “Easy? The problem of moving water uphill without a pump was easy?”

“Oh, yes! Look!”

The boy dumped his box and rummaged through the junk. He came up with a strip of papyrus and showed the old inventor some diagrams and notes. They didn’t make any sense to me, but Daedalus nodded grudgingly. “I see. Not bad.”

“The king loved it!” Perdix said. “He said I might be even smarter than you!”

“Did he now?”

“But I don’t believe that. I’m so glad Mother sent me to study with you! I want to know everything you do.”

“Yes,” Daedalus muttered. “So when I die, you can take my place, eh?”

The boys’ eyes widened. “Oh no, Uncle! But I’ve been thinking…why does a man have to die, anyway?”

The inventor scowled. “It is the way of things, lad. Everything dies but the gods.”

“But why?” the boy insisted. “If you could capture the animus, the soul in another form…well, you’ve told me about your automatons, Uncle. Bulls, eagles, dragons, horses of bronze. Why not a bronze form for a man?”

“No, my boy,” Daedalus said sharply. “You are naïve. Such a thing is impossible.”

“I don’t think so,” Perdix insisted. “With the use of a little magic—”

“Magic? Bah!”

“Yes, Uncle! Magic and mechanics together—with a little work, one could make a body that would look exactly human, only better. I’ve made some notes.”

He handed the old man a thick scroll. Daedalus unfurled it. He read for a long time. His eyes narrowed. He glanced at the boy, then closed the scroll and cleared his throat. “It would never work, my boy. When you’re older, you’ll see.”

“Can I fix that astrolabe, then, Uncle? Are your joints swelling up again?”

The old man’s jaw clenched. “No. Thank you. Now why don’t you run along?”

Perdix didn’t seem to notice the old man’s anger. He snatched a bronze beetle from his mound of stuff and ran to the edge of the tower. A low sill ringed the rim, coming just up to the boy’s knees. The wind was strong.

Move back, I wanted to tell him. But my voice didn’t work.

Perdix wound up the beetle and tossed it into the sky. It spread its wings and hummed away. Perdix laughed with delight.

“Smarter than me,” Daedalus mumbled, too soft for the boy to hear.

“Is it true that your son died flying, Uncle? I heard you made him enormous wings, but they failed.”

Daedalus’s hands clenched. “Take my place,” he muttered.

The wind whipped around the boy, tugging at his clothes, making his hair ripple.

“I would like to fly,” Perdix said. “I’d make my own wings that wouldn’t fail. Do you think I could?”

Maybe it was a dream within my dream, but suddenly I imagined the two-headed god Janus shimmering in the air next to Daedalus, smiling as he tossed a silver key from hand to hand. Choose, he whispered to the old inventor. Choose.

Daedalus picked up another one of the boy’s metal bags. The inventor’s old eyes were red with anger.

“Perdix,” he called. “Catch.”

He tossed the bronze beetle toward the boy. Delighted, Perdix tried to catch it, but the throw was too long. The beetle sailed into the sky, and Perdix reached a little too far. The wind caught him.

Somehow he managed to grab the rim of the tower with his fingers as he fell. “Uncle!” he screamed. “Help me!”

The old man’s face was a mask. He did not move from his spot.

“Go on, Perdix,” Daedalus said softly. “May your own wings. Be quick about it.”

“Uncle!” the boy cried as he lost his grip. He tumbled toward the sea.