The Last Olympian

something logical like that. I let him go.
    Nico curled into a ball and made retching sounds while his throat recovered. Finally he got to his feet, eyeing my sword warily. His own blade was sheathed. I suppose if he’d wanted to kill me, he could’ve done it while I slept. Still, I didn’t trust him.
    “We have to get out of here,” he said.
    “Why?” I said. “Does your dad want to talk to me again?”
    He winced. “Percy, I swear on the River Styx, I didn’t know what he was planning.”
    “You know what your dad is like!”
    “He tricked me. He promised—” Nico held up his hands. “Look . . . right now, we need to leave. I put the guards to sleep, but it won’t last.”
    I wanted to strangle him again. Unfortunately, he was right. We didn’t have time to argue, and I couldn’t escape on my own. He pointed at the wall. A whole section vanished, revealing a corridor.
    “Come on.” Nico led the way.
    I wished I had Annabeth’s invisibility hat, but as it turned out, I didn’t need it. Every time we came to a skeleton guard, Nico just pointed at it, and its glowing eyes dimmed. Unfortunately, the more Nico did it, the more tired he seemed. We walked through a maze of corridors filled with guards. By the time we reached a kitchen staffed by skeletal cooks and servants, I was practically carrying Nico. He managed to put all the dead to sleep but nearly passed out himself. I dragged him out of the servants’ entrance and into the Fields of Asphodel.
    I almost felt relieved until I heard the sound of bronze gongs high in the castle.
    “Alarms,” Nico murmured sleepily.
    “What do we do?”
    He yawned then frowned like he was trying to remember. “How about . . . run?”
    Running with a drowsy child of Hades was more like doing a three-legged race with a life-size rag doll. I lugged him along, holding my sword in front of me. The spirits of the dead made way like the celestial bronze was a blazing fire.
    The sound of gongs rolled across the fields. Ahead loomed the walls of Erebos, but the longer we walked, the farther away they seemed. I was about to collapse from exhaustion when I heard a familiar “WOOOOOF!”
    Mrs. O’Leary bounded out of nowhere and ran circles around us, ready to play.
    “Good girl!” I said. “Can you give us a ride to the Styx?”
    The word Styx got her excited. She probably thought I meant sticks . She jumped a few times, chased her tail just to teach it who was boss, and then calmed down enough for me to push Nico onto her back. I climb aboard, and she raced toward the gates. She leaped straight over the EZ-DEATH line, sending guards sprawling and causing more alarms to blare. Cerberus barked, but he sounded more excited than angry, like: Can I play too?
    Fortunately, he didn’t follow us, and Mrs. O’Leary kept running. She didn’t stop until we were far upriver and the fires of Erebos had disappeared in the murk.
    Nico slid off Mrs. O’Leary’s back and crumpled in a heap on the black sand.
    I took out a square of ambrosia—part of the emergency god-food I always kept with me. It was a little bashed up, but Nico chewed it.
    “Uh,” he mumbled. “Better.”
    “Your powers drain you too much,” I noticed.
    He nodded sleepily. “With great power . . . comes great need to take a nap. Wake me up later.”
    “Whoa, zombie dude.” I caught him before he could pass out again. “We’re at the river. You need to tell me what to do.”
    I fed him the last of my ambrosia, which was a little dangerous. The stuff can heal demigods, but it can also burn us to ashes if we eat too much. Fortunately, it seemed to do the trick. Nico shook his head a few times and struggled to his feet.
    “My father will be coming soon,” he said. “We should hurry.”
    The River Styx’s current swirled with strange objects— broken toys, ripped-up college diplomas, wilted homecoming corsages—all the dreams people had thrown away as they’d passed from life into death. Looking at the black water, I could think of about three million places I’d rather swim.
    “So . . . I just jump in?”
    “You have to prepare yourself first,” Nico said, “or the river will destroy you. It will burn away your body and soul.”
    “Sounds fun,” I muttered.
    “This is no joke,” Nico warned. “There is only one way to stay anchored to your mortal life. You have to . . .”
    He glanced behind me and his eyes widened. I turned and found myself face-to-face with a Greek warrior.
    For