It felt like I was falling faster each second. My descent was speeding up so that when I opened my eyes I could see the sheer rock face rushing past my eyes faster than should have been possible. It almost felt like I was being sucked down a giant drain, and I realized that even if I'd wanted to stop now there was no way I could have. I was in this for good.

The darkness seemed to close in over my head and the weight of the water seemed to push on me from every side. It was cold down here. It felt like all of the heat and life was being sucked out of me and into the water, until I couldn't even see the rock on either side of me. I kept falling into the crushing darkness and suddenly I wasn't sure if I was even traveling through the water anymore.

Then, without warning, my feet hit the ground. I stumbled and fell, Nico's sword skittering out of my grip and across the black grass that covered the ground. I looked up and saw that the sky was grey and dark, with the occasional stalactite hanging from it. The tips just barely penetrated the warm, swampy air and made it clear that the sky here wasn't really the sky, but the bottom of the world.

I'd been here before. And I'd hoped to never be here again – well, at least not until it was my time to die, which I hoped would be a really long time from now. But here I was all over again. I was in the Underworld – more specifically, I was in the Fields of Asphodel. I remembered this place pretty well. It was where everyone who'd just… well, plain lived went. If you weren't particularly good or bad, you went to the Asphodel Fields.

I scrambled to my feet and picked up Nico's sword. All around me, the spirits of the dead ambled past, their voices twittering away. I remembered being here before with Annabeth and Grover. The dead had come up to us and muttered at us, but their voices had sounded far away and we couldn't make out their words. When they'd realized we couldn't understand them or hear them properly, they'd gone on their way.

But this time something was different. This time I could understand them.

I wondered if it was because of Nico. Did I have the ability to understand them because he could? Suddenly the why of it became not so important, though, as I realized that the few dead spirits that had stopped to talk at me had been joined by a few more. And that a even more were heading in our direction.

They seemed almost excited, twittering away so rapidly that even though I could understand their words it was hard to make out what any one of them was saying because they were all talking at once. I began to realize that I might have a pretty serious problem on my hands. The dead were flocking to me like moths to a flame, pressing around me in a circle and I wasn't going to get anywhere with all of them trying to get close to me like I was a movie star and they all wanted my autograph. But unlike fans waiting for an autograph, they weren't going to go away. They wanted me to stay and listen.

But I hadn't come this far just to be waylaid by a bunch of dead people who were excited that they finally had someone to talk to. "Hey!" I shouted, waving Nico's sword around a bit. The spirits backed up enough so that the blade couldn't hit them, looking angry or concerned but still talking. "Move it!" I shouted again, swinging the sword in front of me so they parted and I could walk. They closed in behind me, following me, still talking. Apparently they weren't going to be deterred so easily.

"I don't have time to listen to you," I insisted angrily, still swinging the sword. "I have better things to do. I have to find someone." I wasn't sure if Nico would be in the Asphodel Fields – immediately my eyes snapped to the Fields of Punishment. He wouldn't be there, would he? My fingers went numb at the thought and I shook my head as if I could shake that idea away. No, he couldn't be there. His own father wouldn't put him there. At least, I hoped not.

That thought made me angry, and I waved Nico's sword around again. I really didn't have any time to waste. I had to find him. Never mind that I didn't even know where to start. I ignored the memories of all those nightmares I'd had – the ones where I was lost in the Underworld and trying to find Nico and afraid I would be trapped forever. I shuddered. I really hoped those weren't premonitions.

I turned my attention back to the matter at hand. There was only one way to make sure my nightmares didn't come true, I figured, and that would be to make sure of it myself. I looked out at the dead spirits surrounding me. All of them were muttering and their monotonous voices filled my head like static. There were too many words and too many voices overlaid to make out anything. It was starting to give me a headache. And it wasn't getting me any closer to wherever it was I needed to be.

"All of you had better get out of here!" I shouted at them. "I'm not going to let you slow me down. Unless you know where Nico di Angelo is, get out of my way and leave me alone!" Without warning I swung Nico's sword through the nearest spirit, a bland-faced woman with her hair in a bun who was murmuring on and on about paperwork. As the blade went through her she wavered and then exploded in a shower of gray dust. For a minute I felt terrible – she hadn't exactly been trying to attack me. But I had to do something or I was never going to get out of the Asphodel Fields to find Nico.

Besides, I somehow knew that she wasn't gone forever, anyway. There's no way you can really get rid of someone who's already dead, after all – you can't even get rid of some things that are living (or near enough to it). That's why the monsters of myth keep coming back even after they've been killed. They always manage to reform and reappear again. So I imagined that the woman's spirit would rematerialize later, once all of the dust had coagulated back into her image, and she'd go right on muttering about paperwork and trying to find the next person whose ear she could talk off.

But right now, the other spirits were looking at me and the sword like they might be having second thoughts and talking to me, now that it was clear I meant business. So at least dead spirits didn't like being reduced to dust. Good. I brandished Nico's sword like I meant it this time. I wasn't afraid to start turning every spirit in sight into dust, if that was what it took.

Most of them appeared to get the hint and started backing away, though they were still muttering angrily. Some looked dejected or sad that I wouldn't listen to them, but I didn't have time to feel sorry for them now. If I stayed to listen to them I really would die here. I was sure of that.

As they backed away and started drifting off, it was easier to pick out single voices and make out what they were saying. And amidst the angry muttering I suddenly heard the undertones of a voice I recognized. For a minute I didn't know who it belonged to – I just knew that I recognized it. I looked through the thinning crowd of half-transparent faces, searching for one that I might know.

Finally I saw him. It was Castor – one of Dionysus' twin sons who had been killed during the Battle of the Labyrinth. In the gray, perpetually waning light I could just make out his pale face and blond hair. I bit my lip as my stomach seemed to fill with frozen lead. I hadn't really ever talked to him when he was alive. I hadn't even known which of the twins was which until one of them had died. I'd felt horrible when I'd realized that, watching his body burn atop its funeral pyre the night we laid those who'd fallen in battle to rest. I wondered what his brother Pollux would think if he knew that I had the chance to talk to his twin.

I realized I had to talk to him – maybe I could get him to help. I had to try. "Castor!" I called, trying to get his attention. "Castor, it's Percy!" He turned slowly towards me, eyes cold and dead with no recognition in them. "It's Percy Jackson, we were campers together," I went on, hoping to jog his memory. "We're both half-bloods, and I need your help."

He looked balefully at Nico's sword. I smiled a little ruefully and lowered it to my side. "Sorry," I muttered. I didn't want him to think I'd hurt him – not when he might be able to help. He had to know who Nico was. I mean, the whole camp pretty much knew who had created that big fissure in the dining pavilion. He'd at least know who I was talking about even if they hadn't met.

The problem was, would he even remember his life, or who I was? Would he care enough to help? If I'd noticed one thing, it was that the dead didn't seem to care much about the living. They were trapped inside their own little bubble-universes, wandering around all wrapped up in whatever had bugged them in life. Getting them to care about things that were going on in the living world was pretty difficult. But it could be done – Nico had gotten dead spirits to help him before and so, I realized, had I. I hoped that meant that I might have more luck convincing Castor to help than I might have otherwise. And maybe being a half-blood meant that Castor would be more coherent than your regular spirit off the street (or, well, out of the fields). Bianca had seemed pretty with it, so maybe Castor would remember –

"Nico," I said, staring right into Castor's blue eyes and trying to keep him interested in what I was saying by sheer force of will alone. "Nico di Angelo, Hades' son. You know who he is, right?"

For a minute he just kept staring back at me, blank-eyed. I felt my stomach drop – but then his eyes seemed to grow a little brighter, and Castor nodded. "Nico," he repeated. "Nico di Angelo."

Well, it was a start. I nodded too, emphatically. "Yes. You know him. Have you seen him? Do you know where he is?"

Castor shook his head. "No. I don't know." My stomach dropped again, so far that it felt like it was somewhere in the vicinity of the core of the earth about now. I guess there was no reason I should've expected him to know, but I'd still gotten my hopes up without meaning to.

"Percy Jackson."

I looked up at the new voice. It was also one I recognized, better than I recognized Castor's. This one I could put a name to even before I saw the familiar face. It was Lee Fletcher, the head – well, former head – of the Apollo Cabin. He was standing in front of me only a couple of feet away.

Suddenly the lead feeling in my stomach was back. I guess I'd figured the Underworld was a pretty big place. What were the chances of running into people I knew down here? I'd thought I'd already been pushing luck by running into Castor. But the spirits of the dead were obviously attracted to me somehow, probably because Nico's powers made me able to understand them. I guess it made sense that the spirits of dead half-bloods would be attracted to my presence too, but I guess I'd also really been hoping I wouldn't have to see people I knew again all the same. It was weird – I felt like I should be glad for the familiar faces, but they only made me feel guilty and uncomfortable.

"You're alive," he said. It sounded almost like an accusation, or maybe like he was disappointed. That wasn't exactly helping with the feeling uncomfortable part of things for my part.

I nodded. "Yeah, I am. Look, Lee…" I went on in a rush, figuring if I was talking then I didn't have to be thinking about how bad I felt. "You remember Nico, right? I really need to find him."

He frowned. "Why?"

That was the million-dollar question, wasn't it? I swallowed and decided to go with the easiest explanation. "We have a plan. You know, to defeat Kronos." I lowered my voice. "Nico's really important to it."

"He's dead," Castor said dully, like maybe I didn't know that already. I wanted to stamp my foot and wave my arms around and tell him of course I knew that. Why else would I be looking for him here?

Instead I just nodded and looked from Castor to Lee and back again. "I know. But I have to bring him back."

"How?" Lee asked, and the question made my stomach churn.

"I don't know," I admitted honestly, thinking I really wasn't going to get anywhere if I didn't come up with a plan, and soon. "But I have to try. I mean, I know it can be done. It's been done before – er, well, I know somebody tried, before," I corrected, remembering the story. "But Hades let someone go."

"That was different," Lee said slowly. "That was for love."

"… I know," I said, feeling my insides churn themselves up into a Percy's Stomach Smoothie. I scuffed one foot in the beaten dirt amidst the black grass and looked at Lee quietly for a minute. Should I tell him? Would that convince him to help me?

Well, really, what did I have to lose? "This kind of is, too," I said.

Silence.

"Oh," Castor finally said, quietly. "You?"

I nodded, feeling my face turning red. "Yeah." I wished it wouldn't do that every time I told someone I liked Nico. Wasn't it supposed to get better after a while or something?

"That makes things different," Lee suddenly said. Did that mean he was going to help, after all? He looked at the Stygian iron sword in my hand and said, "That's his."

"Yeah."

"You can use it to find him."

I stared at Lee. I could? Why hadn't anyone told me this before? "How?"

He shrugged. "You just can. It knows the way. It's powerful down here."

Well, that was helpful, I thought sarcastically. Nico's sword knew the way? I raised the sword a little – the two spirits backed away warily, but didn't flee – and looked at the flat, dull blade. It just looked like a sword to me. I wasn't sure how I was supposed to use it to find Nico…

I suddenly got a mental image of the sword pointing in one direction, the blade resting at the point where the horizon met the flat, black hills. The blade in my mind pulled at my arm like an insistent dog on a leash. I blinked – was that how I was supposed to do it? Just… dowse for Nico like people in books dowsed for water?

My thoughts were interrupted by Lee. "But once you find him," he said, "you still need a way."

"A way?" I frowned. "A way what?"

"To bring him back," Castor said, matter-of-factly. "You can't just take him."

Lee smiled grimly. "Hades isn't going to just let you waltz in there and take his son."

"He won't let you take anybody," Castor added helpfully.

I wanted to scream. So I was back to square one. Stuck in the Underworld with maybe a way to find Nico, but no way to get him out.

"But it has been done before," Lee said, echoing what I'd said earlier. "He knows a way."

I felt my heartbeat speed up as I looked at him fiercely, eyes wide. "He? Who?" If he knew someone who could help me, he'd better tell me about it!

Castor frowned. "My father doesn't like him, though. I don't like him either."

Lee glanced at Castor, then shrugged. "He may have forsaken your father, but he hasn't forsaken mine."

I clenched my teeth, resisting the urge to drop Nico's sword and start shaking the ghost-Lee by the shoulders. I got the feeling that might not work very well, but it didn't make me want to do it any less. "Who?" I asked again. "Someone here? Can you take me to him?"

Le nodded. "Orpheus," he said solemnly. "Orpheus knows the way." He looked over at Castor, who was looking like he wanted to turn on his heel and leave. "I can tell you where he is."