We stood in the shadows of Valencia Boulevard, looking up at gold letters etched in black marble: DOA RECORDING STUDIOS.

Underneath, stenciled on the glass doors: NO SOLICI-TORS. NO LOITERING. NO LIVING.

It was almost midnight, but the lobby was brightly lit and full of people. Behind the security desk sat a tough-looking guard with sunglasses and an earpiece.

I turned to my friends. "Okay. You remember the plan." "The plan," Jordan ginned. "Yeah. I love the plan." Annabeth said, "What happens if the plan doesn't work?" "Don't think negative."

"Right," she said. "We're entering the Land of the Dead, and I shouldn't think negative."

I took the pearls out of my pocket, the three milky spheres the Nereid had given me in Santa Monica. They didn't seem like much of a backup in case something went wrong.

Annabeth put her hand on my shoulder. "I'm sorry, Percy. You're right, we'll make it. It'll be fine."

She gave Jordan a nudge.

"Oh, right!" he chimed in. "We got this far. We'll find the master bolt and save our mom. No problem."

I slipped the pearls back in my pocket. "Let's whoop some Underworld butt."

We walked inside the DOA lobby.

Muzak played softly on hidden speakers. The carpet and walls were steel gray. Pencil cactuses grew in the corners like skeleton hands. The furniture was black leather, and every seat was taken. There were people sitting on couches, people standing up, people staring out the windows or wait-ing for the elevator. Nobody moved, or talked, or did much of anything. Out of the corner of my eye, I could see them all just fine, but if I focused on any one of them in partic-ular, they started looking ... transparent. I could see right through their bodies.

The security guard's desk was a raised podium, so we had to look up at him.

He was tall and elegant, with chocolate-colored skin and bleached-blond hair shaved military style. He wore tortoiseshell shades and a silk Italian suit that matched his hair. A black rose was pinned to his lapel under a silver name tag.

help you little dead ones?"

His question caught in my stomach like a fastball. I looked at Annabeth for support. "We want to go the Underworld," she said.

Charon's mouth twitched. "Well, that's refreshing."

"It is?" she asked.

"Straightforward and honest. No screaming. No 'There must be a mistake, Mr. Charon.'" He looked us over. "How did you die, then?"

I nudged Jordan.

"Oh," he said. "Um ... drowned ... in the bathtub." "All three of you?" Charon asked. We shook our heads.

"Suicide pact." Charon looked mildly impressed. "I don't suppose you have coins for passage. Normally, with adults, you see, I could charge your American Express, or add the ferry price to your last cable bill. But with children ... alas, you never die prepared. Suppose you'll have to take a seat for a few centuries."

"Oh, but we have coins." I set three golden drachmas on the counter, part of the stash I'd found in Crusty's office desk.

"Well, now ..." Charon moistened his lips. "Real drach-mas. Real golden drachmas. I haven't seen these in ..."

His fingers hovered greedily over the coins. We were so close.

He sighed. "The boat's almost full, anyway. I might as well add you three and be off." He stood, scooped up our money, and said, "Come along."

We pushed through the crowd of waiting spirits, who started grabbing at our clothes like the wind, their voices whispering things I couldn't make out. Charon shoved them out of the way, grumbling, "Freeloaders."

He escorted us into the elevator, which was already crowded with souls of the dead, each one holding a green boarding pass. Charon grabbed two spirits who were trying to get on with us and pushed them back into the lobby.

"Right. Now, no one get any ideas while I'm gone," he announced to the waiting room. "And if anyone moves the dial off my easy-listening station again, I'll make sure you're here for another thousand years. Understand?"

He shut the doors. He put a key card into a slot in the elevator panel and we started to descend. "What happens to the spirits waiting in the lobby?" Annabeth asked.

"Nothing," Charon said.

"For how long?"

"Forever, or until I'm feeling generous." "Oh," she said. "That's ... fair."

I got a sudden dizzy feeling. We weren't going down anymore, but forward. The air turned misty. Spirits around me started changing shape. Their modern clothes flickered, turning into gray hooded robes. The floor of the elevator began swaying.

I blinked hard. When I opened my eyes, Charon's creamy Italian suit had been replaced by a long black robe. His tortoiseshell glasses were gone. Where his eyes should've been were empty sockets-like Ares's eyes, except Charon's were totally dark, full of night and death and despair. When I blinked again, the elevator wasn't an elevator anymore. We were standing in a wooden barge. Charon was poling us across a dark, oily river, swirling with bones, dead fish, and other, stranger things- plastic dolls, crushed car-nations, soggy diplomas with gilt edges.

"The River Styx," Annabeth murmured. "It's so ..."

"Polluted," Charon said. "For thousands of years, you humans have been throwing in everything as you come across-hopes, dreams, wishes that never came true. Irresponsible waste management, if you ask me."

Mist curled off the filthy water. Above us, almost lost in the gloom, was a ceiling of stalactites. Ahead, the far shore glimmered with greenish light, the color of poison.

Panic closed up my throat. What was I doing here? These people around me ... they were dead.

Annabeth grabbed hold of my hand. Under normal circumstances, this would've embarrassed me, but I understood how she felt. She wanted reassurance that somebody else was alive on this boat

I found myself muttering a prayer, though I wasn't quite sure who I was praying to. Down here, only one god mat-tered, and he was the one I had come to confront.

The shoreline of the Underworld came into view. Craggy rocks and black volcanic sand stretched inland about a hundred yards to the base of a high stone wall, which marched off in either direction as far as we could see. A sound came from somewhere nearby in the green gloom, echoing off the stones-the howl of a large animal.

The bottom of our boat slid onto the black sand. The dead began to disembark. A woman holding a little girl's hand. An old man and an old woman hobbling along arm in arm. A boy no older than I was, shuffling silently along in his gray robe.

He counted our golden coins into his pouch, then took up his pole. He warbled something that sounded like a Barry Manilow song as he ferried the empty barge back across the river.

We followed the spirits up a well-worn path.

I'm not sure what I was expecting-Pearly Gates, or a big black portcullis, or something. But the entrance to the Underworld looked like a cross between airport security and the Jersey Turnpike.

There were three separate entrances under one huge black archway that said YOU ARE NOW ENTERING EREBUS. Each entrance had a pass-through metal detector with secu-rity cameras mounted on top. Beyond this were tollbooths manned by black-robed ghouls like Charon.

The howling of the hungry animal was really loud now, but I couldn't see where it was coming from. The three-headed dog, Cerberus, who was supposed to guard Hades's door, was nowhere to be seen.

The dead queued up in the three lines, two marked ATTENDANT ON DUTY, and one marked EZ DEATH. The EZ DEATH line was moving right along. The other two were crawling.

"What do you figure?" I asked Annabeth.

"The fast line must go straight to the Asphodel Fields," she said. "No contest. They don't want to risk judgment from the court, because it might go against them."

"There's a court for dead people?"

"Yeah. Three judges. They switch around who sits on the bench. King Minos, Thomas Jefferson, Shakespeare-people like that. Sometimes they look at a life and decide that person needs a special reward-the Fields of Elysium. Sometimes they decide on punishment. But most people, well, they just lived. Nothing special, good or bad. So they go to the Asphodel Fields."

"And do what?"

Jordan said, "Imagine standing in a wheat field in Kansas. Forever." "Harsh," I said.

"Not as harsh as that," Jordan muttered. "Look."

A couple of black-robbed ghouls had pulled aside one spirit and were frisking him at the security desk. The face of the dead man looked vaguely familiar.

"He's that preacher who made the news, remember?" Jordan asked.

"Oh, yeah." I did remember now. We'd seen him on TV a couple of times at the Yancy Academy dorm. He was this annoying televangelist from upstate New York who'd raised millions of dollars for orphanages and then got caught spending the money on stuff for his mansion, like gold-plated toilet seats, and an indoor putt-putt golf course. He'd died in a police chase when his "Lamborghini for the Lord" went off a cliff.

I said, "What're they doing to him?"

"Special punishment from Hades," Jordan guessed. "The really bad people get his personal attention as soon as they arrive. The Fur-the Kindly Ones will set up an eternal torture for him."

The thought of the Furies made me shudder. I realized I was in their home territory now. Old Mrs. Dodds would be licking her lips with anticipation.

"But if he's a preacher," I said, "and he believes in a different hell... ."

Grover shrugged. "Who says he's seeing this place the way we're seeing it? Humans see what they want to see. You're very stubborn-er, persistent, that way."

We got closer to the gates. The howling was so loud now it shook the ground at my feet, but I still couldn't figure out where it was coming from.

Then, about fifty feet in front of us, the green mist shimmered. Standing just where the path split into three lanes was an enormous shadowy monster.

I hadn't seen it before because it was half transparent, like the dead. Until it moved, it blended with whatever was behind it. Only its eyes and teeth looked solid. And it was staring straight at me.

My jaw hung open. All I could think to say was, "He's a Rottweiler."

I'd always imagined Cerberus as a big black mastiff. But he was obviously a purebred Rottweiler, except of course that he was twice the size of a woolly mammoth, mostly invisible, and had three heads.

The dead walked right up to him-no fear at all. The ATTENDANT ON DUTY lines parted on either side of him. The EZ DEATH spirits walked right between his front paws and under his belly, which they could do without even crouching.

"I'm starting to see him better," I muttered. "Why is that?"

"I think ..." Annabeth moistened her lips. "I'm afraid it's because we're getting closer to being dead." The dog's middle head craned toward us. It sniffed the air and growled.

"It can smell the living," I said.

"But that's okay," Jordan said, confident next to me. "Because we have a plan."

"Right," Annabeth said. I'd never heard her voice sound quite so small. "A plan."

We moved toward the monster.

The middle head snarled at us, then barked so loud my eyeballs rattled. "Can you understand it?" I asked Jordan.

"Oh yeah," he said. "I can understand it."

"What's it saying?"

"I don't think humans have a four-letter word that translates, exactly."

I took the big stick out of my backpack-a bedpost I'd broken off Crusty's Safari Deluxe floor model. I held it up, and tried to channel happy dog thoughts toward Cerberus-Alpo commercials, cute little pup-pies, fire hydrants. I tried to smile, like I wasn't about to die.

"Hey, Big Fella," I called up. "I bet they don't play with you much." "GROWWWLLLL!"

"Good boy," I said weakly.

I waved the stick. The dog's middle head followed the movement. The other two heads trained their eyes on me, completely ignoring the spirits. I had Cerberus's undivided attention. I wasn't sure that was a good thing.

"Fetch!" I threw the stick into the gloom, a good solid throw. I heard it go ker-sploosh in the River Styx.

Cerberus glared at me, unimpressed. His eyes were baleful and cold.

So much for the plan.

Cerberus was now making a new kind of growl, deeper down in his three throats.

"Um," Jordan said. "Percy?"

"Yeah?"

"I just thought you'd want to know."

"Yeah?"

"Cerberus? He's saying you and Annabethgot ten seconds to pray to the god of our choice. After that... well ... he's hungry. He only likes me because of my patron Hecate."

"Wait!" Annabeth said. She started rifling through her pack.

Uh-oh, I thought.

"Five seconds," Jordan said. "Do we run now?"

Annabeth produced a red rubber ball the size of a grapefruit. It was labeled WATERLAND, DENVER, CO. Before I could stop her, she raised the ball and marched straight up to Cerberus.

She shouted, "See the ball? You want the ball, Cerberus? Sit!"

Cerberus looked as stunned as we were.

All three of his heads cocked sideways. Six nostrils dilated.

"Sit!" Annabeth called again.

I was sure that any moment she would become the world's largest Milkbone dog biscuit.

But instead, Cerberus licked his three sets of lips, shifted on his haunches, and sat, immediately crushing a dozen spirits who'd been passing underneath him in the EZ DEATH line. The spirits made muffled hisses as they dissi-pated, like the air let out of tires.

Annabeth said, "Good boy!" She threw Cerberus the ball.

He caught it in his middle mouth. It was barely big enough for him to chew, and the other heads started snap-ping at the middle, trying to get the new toy.

"Drop it.'" Annabeth ordered.

Cerberus's heads stopped fighting and looked at her. The ball was wedged between two of his teeth like a tiny piece of gum. He made a loud, scary whimper, then dropped the ball, now slimy and bitten nearly in half, at Annabeth's feet.

"Good boy." She picked up the ball, ignoring the mon-ster spit all over it.

She turned toward us. "Go now. EZ DEATH line-it's faster."

I said, "But-"

"Now.'" She ordered, in the same tone she was using on the dog. Jordan and I inched forward warily.

Cerberus started to growl.

"Stay!" Annabeth ordered the monster. "If you want the ball, stay!" Cerberus whimpered, but he stayed where he was.

"What about you?" I asked Annabeth as we passed her.

"I know what I'm doing, Percy," she muttered. "At least, I'm pretty sure... ." Grover and I walked between the monster's legs.

Please, Annabeth, I prayed. Don't tell him to sit again.

We made it through. Cerberus wasn't any less scary-looking from the back.

Annabeth said, "Good dog!"

She held up the tattered red ball, and probably came to the same conclusion I did-if she rewarded Cerberus, there'd be nothing left for another trick.

She threw the ball anyway. The monster's left mouth immediately snatched it up, only to be attacked by the middle head, while the right head moaned in protest.

While the monster was distracted, Annabeth walked briskly under its belly and joined us at the metal detector.

"How did you do that?" I asked her, amazed.

"Obedience school," she said breathlessly, and I was sur-prised to see there were tears in her eyes. "When I was little, at my dad's house, we had a Doberman... ."

"Never mind that," Jordan said, tugging at my shirt. "Come on!"

We were about to bolt through the EZ DEATH line when Cerberus moaned pitifully from all three mouths. Annabeth stopped.

She turned to face the dog, which had done a one-eighty to look at us.

Cerberus panted expectantly, the tiny red ball in pieces in a puddle of drool at its feet. "Good boy," Annabeth said, but her voice sounded melancholy and uncertain.

The monster's heads turned sideways, as if worried about her.

"I'll bring you another ball soon," Annabeth promised faintly. "Would you like that?"

The monster whimpered. I didn't need to speak dog to know Cerberus was still waiting for the ball.

"Good dog. I'll come visit you soon. I-I promise." Annabeth turned to us. "Let's go."

Jordan and I pushed through the metal detector, which immediately screamed and set off flashing red lights. "Unauthorized possessions! Magic detected!"

Cerberus started to bark.

We burst through the EZ DEATH gate, which started even more alarms blaring, and raced into the Underworld.

A few minutes later, we were hiding, out of breath, in the rotten trunk of an immense black tree as security ghouls scuttled past, yelling for backup from the Furies.

Grover murmured, "Well, Percy, what have we learned today?"

"That three-headed dogs prefer red rubber balls over sticks?"

"No," Jordan told me. "We've learned that your plans really, really bite!"

I wasn't sure about that. I thought maybe Annabeth and I had both had the right idea. Even here in the Underworld, everybody-even monsters-needed a little attention once in a while.

I thought about that as we waited for the ghouls to pass. I pretended not to see Annabeth wipe a tear from her cheek as she listened to the mournful keening of Cerberus in the distance, longing for his new friend.

Imagine the largest concert crowd you've ever seen, a football field packed with a million fans.

Now imagine a field a million times that big, packed with people, and imagine the electricity has gone out, and there is no noise, no light, no beach ball bouncing around over the crowd. Something tragic has happened backstage. Whispering masses of people are just milling around in the shadows, waiting for a concert that will never start.

If you can picture that, you have a pretty good idea what the Fields of Asphodel looked like. The black grass had been trampled by eons of dead feet. A warm, moist wind blew like the breath of a swamp. Black trees-Jordan told me they were poplars-grew in clumps here and there.

The cavern ceiling was so high above us it might've been a bank of storm clouds, except for the stalactites, which glowed faint gray and looked wickedly pointed. I tried not to imagine they'd fall on us at any moment, but dotted around the fields were several that had fallen and impaled themselves in the black grass. I guess the dead didn't have to worry about little hazards like being speared by stalactites the size of booster rockets.

Annabeth,Jordan, and I tried to blend into the crowd, keeping an eye out for security ghouls. I couldn't help look-ing for familiar faces among the spirits of Asphodel, but the dead are hard to look at. Their faces shimmer. They all look slightly angry or confused. They will come up to you and speak, but their voices sound like chatter, like bats twitter-ing. Once they realize you can't understand them(or in Jordan's case don't care what they're saying), they frown and move away.

The dead aren't scary. They're just sad.

We crept along, following the line of new arrivals that snaked from the main gates toward a black- tented pavilion with a banner that read:

JUDGMENTS FOR ELYSIUM AND ETERNAL DAMNATION Welcome, Newly Deceased!

Out the back of the tent came two much smaller lines.

To the left, spirits flanked by security ghouls were marched down a rocky path toward the Fields of Punish-ment, which glowed and smoked in the distance, a vast, cracked wasteland with rivers of lava and minefields and miles of barbed wire separating the different torture areas. Even from far away, I could see people being chased by hellhounds, burned at the stake, forced to run naked through cactus patches or listen to opera music. I could just make out a tiny hill, with the ant-size figure of Sisyphus struggling to move his boulder to the top. And I saw worse tortures, too-things I don't want to describe.

The line coming from the right side of the judgment pavilion was much better. This one led down toward a small valley surrounded by walls-a gated community, which seemed to be the only happy part of the Underworld. Beyond the security gate were neighborhoods of beautiful houses from every time period in history, Roman villas and medieval castles and Victorian mansions. Silver and gold flowers bloomed on the lawns. The grass rippled in rainbow colors. I could hear laughter and smell barbecue cooking.

Elysium.

In the middle of that valley was a glittering blue lake, with three small islands like a vacation resort in the Bahamas. The Isles of the Blest, for people who had chosen to be reborn three times, and three times achieved Elysium. Immediately I knew that's where I wanted to go when I died.

"That's what it's all about," Annabeth said, like she was reading my thoughts. "That's the place for heroes."

But I thought of how few people there were in Elysium, how tiny it was compared to the Fields of Asphodel or even the Fields of Punishment. So few people did good in their lives. It was depressing.

We left the judgment pavilion and moved deeper into the Asphodel Fields. It got darker. The colors faded from our clothes. The crowds of chattering spirits began to thin.

After a few miles of walking, we began to hear a familiar screech in the distance. Looming on the horizon was a palace of glittering black obsidian. Above the parapets swirled three dark batlike creatures: the Furies. I got the feeling they were waiting for us.

"I suppose it's too late to turn back," Jordan said wistfully. "We'll be okay." I tried to sound confident.

"Maybe we should search some of the other places first," Jordan joked. "Like, Elysium, for instance ..."

"Come on, wizard boy." Annabeth grabbed his arm.

Jordan yelped. The sneakers from Luke at the beginning of the quest burst out of his backpack and sprouted wings and shot forward, "Jordan," Annabeth chided. "Stop messing around." "But I didn't-"

The shoes were flapping like crazy now. They levitated off the ground and started flying "Maia!" he yelled, but the magic word seemed to have no effect. "Maia, already! They were picking up speed, skidding downhill like a bobsled.

We ran after them.

The slope got steeper. Jordan picked up speed. Annabeth and I had to sprint to keep up. The cavern walls narrowed on either side, and I realized we'd entered some kind of side tunnel. No black grass or trees now, just rock underfoot, and the dim light of the stalactites above.

The tunnel got darker and colder. The hairs on my arms bristled. It smelled evil down here. It made me think of things I shouldn't even know about-blood spilled on an ancient stone altar, the foul breath of a murderer.

Then I saw what was ahead of us, and I stopped dead in my tracks.

The tunnel widened into a huge dark cavern, and in the middle was a chasm the size of a city flying sneakers had sped into the darkness, down into the chasm. We all collapsed, exhausted, on the obsidian gravel. My limbs felt like lead. Even my backpack seemed heavier, as if somebody had filled it with rocks.

I heard something-a deep whisper in the darkness.

Another few seconds, and Annabeth said, "Percy, this place-"

"Shh." I stood.

The sound was getting louder, a muttering, evil voice from far, far below us. Coming from the pit.

Grover sat up. "Wh-what's that noise?"

Annabeth heard it too, now. I could see it in her eyes. "Tartarus. The entrance to Tartarus." I uncapped Anaklusmos.

The bronze sword expanded, gleaming in the darkness, and the evil voice seemed to falter, just for a moment, before resuming its chant.

I could almost make out words now, ancient, ancient words, older even than Greek. As if ... "Magic," Jordan said.

"We have to get out of here," Annabeth said.

We broke into a run.

Not a moment too soon.

A cold blast of wind pulled at our backs, as if the entire pit were inhaling. For a terrifying moment, I lost ground, my feet slipping in the gravel. If we'd been any closer to the edge, we would've been sucked in.

We kept struggling forward, and finally reached the top of the tunnel, where the cavern widened out into the Fields of Asphodel. The wind died. A wail of outrage echoed from deep in the tunnel. Something was not happy we'd gotten away.

"I capped my sword, put the pen back in my pocket. "Let's keep going."

The Furies circled the parapets, high in the gloom. The outer walls of the fortress glittered black, and the two-story-tall bronze gates stood wide open.

Inside the courtyard was the strangest garden I'd ever seen. Multicolored mushrooms, poisonous shrubs, and weird luminous plants grew without sunlight. Precious jew-els made up for the lack of flowers, piles of rubies as big as my fist, clumps of raw diamonds. Standing here and there like frozen party guests were Medusa's garden statues- petrified children, satyrs, and centaurs-all smiling gro-tesquely.

In the center of the garden was an orchard of pomegranate trees, their orange blooms neon bright in the dark. "The garden of Persephone," Annabeth said. "Keep walking."

I understood why she wanted to move on. The tart smell of those pomegranates was almost overwhelming. I had a sudden desire to eat them, but then I remembered the story of Persephone. One bite of Underworld food, and we would never be able to leave.

We walked up the steps of the palace, between black columns, through a black marble portico, and into the house of Hades. The entry hall had a polished bronze floor, which seemed to boil in the reflected torchlight. There was no ceiling, just the cavern roof, far above. I guess they never had to worry about rain down here.

Every side doorway was guarded by a skeleton in mili-tary gear. Some wore Greek armor, some British redcoat uniforms, some camouflage with tattered American flags on the shoulders. They carried spears or muskets or M-16s. None of them bothered us, but their hollow eye sockets fol-lowed us as we walked down the hall, toward the big set of doors at the opposite end.

Two U.S. Marine skeletons guarded the doors. They grinned down at us, rocket-propelled grenade launchers held across their chests.

My backpack weighed a ton now. I couldn't figure out why. I wanted to open it, check to see if I had somehow picked up a stray bowling ball, but this wasn't the time.