“No,” Tyson said, fiddling with the strap of his duffel bag. “Bad smell.”

Annabeth frowned. “I don’t smell anything.”

“Cyclopes are like satyrs,” I said. “They can smell monsters. Isn’t that right, Tyson?”

He nodded nervously. Now that we were away from Camp Half-Blood, the Mist had distorted his face again. Unless I concentrated very hard, it seemed that he had two eyes instead of one.

“Okay,” Annabeth said. “So what exactly do you smell?”

“Something bad,” Tyson answered.

“Great,” Annabeth grumbled. “That clears it up.”

We came outside on the swimming pool level. There were rows of empty deck chairs and a bar closed off with a chain curtain. The water in the pool glowed eerily, sloshing back and forth from the motion of the ship.

Above us fore and aft were more levels—a climbing wall, a putt-putt golf course, a revolving restaurant, but no sign of life.

And yet … I sensed something familiar. Something dangerous. I had the feeling that if I weren’t so tired and burned out on adrenaline from our long night, I might be able to put a name to what was wrong.

“We need a hiding place,” I said. “Somewhere safe to sleep.”

“Sleep,” Annabeth agreed wearily.

We explored a few more corridors until we found an empty suite on the ninth level. The door was open, which struck me as weird. There was a basket of chocolate goodies on the table, an iced-down bottle of sparkling cider on the nightstand, and a mint on the pillow with a handwritten note that said: Enjoy your cruise!

We opened our duffel bags for the first time and found that Hermes really had thought of everything—extra clothes, toiletries, camp rations, a Ziploc bag full of cash, a leather pouch full of golden drachmas. He’d even managed to pack Tyson’s oilcloth with his tools and metal bits, and Annabeth’s cap of invisibility, which made them both feel a lot better.

“I’ll be next door,” Annabeth said. “You guys don’t drink or eat anything.”

“You think this place is enchanted?”

She frowned. “I don’t know. Something isn’t right. Just … be careful.”

We locked our doors.

Tyson crashed on the couch. He tinkered for a few minutes on his metalworking project—which he still wouldn’t show me—but soon enough he was yawning. He wrapped up his oilcloth and passed out.

I lay on the bed and stared out the porthole. I thought I heard voices out in the hallway, like whispering. I knew that couldn’t be. We’d walked all over the ship and had seen nobody. But the voices kept me awake. They reminded me of my trip to the Underworld—the way the spirits of the dead sounded as they drifted past.

Finally my weariness got the best of me. I fell asleep … and had my worst dream yet.

I was standing in a cavern at the edge of an enormous pit. I knew the place too well. The entrance to Tartarus. And I recognized the cold laugh that echoed from the darkness below.

If it isn’t the young hero. The voice was like a knife blade scraping across stone. On his way to another great victory.

I wanted to shout at Kronos to leave me alone. I wanted to draw Riptide and strike him down. But I couldn’t move. And even if I could, how could I kill something that had already been destroyed—chopped to pieces and cast into eternal darkness?

Don’t let me stop you, the titan said. Perhaps this time, when you fail, you’ll wonder if it’s worthwhile slaving for the gods. How exactly has your father shown his appreciation lately?

His laughter filled the cavern, and suddenly the scene changed.

It was a different cave—Grover’s bedroom prison in the Cyclops’s lair.

Grover was sitting at the loom in his soiled wedding dress, madly unraveling the threads of the unfinished bridal train.

“Honeypie!” the monster shouted from behind the boulder.

Grover yelped and began weaving the threads back together.

The room shook as the boulder was pushed aside. Looming in the doorway was a Cyclops so huge he made Tyson look vertically challenged. He had jagged yellow teeth and gnarled hands as big as my whole body. He wore a faded purple T-shirt that said WORLD SHEEP EXPO 2001. He must’ve been at least fifteen feet tall, but the most startling thing was his enormous milky eye, scarred and webbed with cataracts. If he wasn’t completely blind, he had to be pretty darn close.

“What are you doing?” the monster demanded.

“Nothing!” Grover said in his falsetto voice. “Just weaving my bridal train, as you can see.”

The Cyclops stuck one hand into the room and groped around until he found the loom. He pawed at the cloth. “It hasn’t gotten any longer!”

“Oh, um, yes it has, dearest. See? I’ve added at least an inch.”

“Too many delays!” the monster bellowed. Then he sniffed the air. “You smell good! Like goats!”

“Oh.” Grover forced a weak giggle. “Do you like it? It’s Eau de Chevre. I wore it just for you.”

“Mmmm!” The Cyclops bared his pointed teeth. “Good enough to eat!”

“Oh, you’re such a flirt!”

“No more delays!”

“But dear, I’m not done!”

“Tomorrow!”

“No, no. Ten more days.”

“Five!”

“Oh, well, seven then. If you insist.”

“Seven! That is less than five, right?”

“Certainly. Oh yes.”

The monster grumbled, still not happy with his deal, but he left Grover to his weaving and rolled the boulder back into place.

Grover closed his eyes and took a shaky breath, trying to calm his nerves.

“Hurry, Percy,” he muttered. “Please, please, please!”

I woke to a ship’s whistle and a voice on the intercom— some guy with an Australian accent who sounded way too happy.

“Good morning, passengers! We’ll be at sea all day today. Excellent weather for the poolside mambo party! Don’t forget million-dollar bingo in the Kraken Lounge at one o’clock, and for our special guests, disemboweling practice on the Promenade!”

I sat up in bed. “What did he say?”

Tyson groaned, still half asleep. He was lying facedown on the couch, his feet so far over the edge they were in the bathroom. “The happy man said … bowling practice?”

I hoped he was right, but then there was an urgent knock on the suite’s interior door.

Annabeth stuck her head in—her blond hair in a rat’s nest. “Disemboweling practice?”

Once we were all dressed, we ventured out into the ship and were surprised to see other people. A dozen senior citizens were heading to breakfast. A dad was taking his kids to the pool for a morning swim. Crew members in crisp white uniforms strolled the deck, tipping their hats to the passengers.

Nobody asked who we were. Nobody paid us much attention. But there was something wrong.

As the family of swimmers passed us, the dad told his kids: “We are on a cruise. We are having fun.”

“Yes,” his three kids said in unison, their expressions blank. “We are having a blast. We will swim in the pool.”

They wandered off.

“Good morning,” a crew member told us, his eyes glazed. “We are all enjoying ourselves aboard the Princess Andromeda. Have a nice day.” He drifted away.

“Percy, this is weird,” Annabeth whispered. “They’re all in some kind of trance.”

Then we passed a cafeteria and saw our first monster. It was a hellhound—a black mastiff with its front paws up on the buffet line and its muzzle buried in the scrambled eggs. It must’ve been young, because it was small compared to most—no bigger than a grizzly bear. Still, my blood turned cold. I’d almost gotten killed by one of those before.

The weird thing was: a middle-aged couple was standing in the buffet line right behind the devil dog, patiently waiting their turn for the eggs. They didn’t seem to notice anything out of the ordinary.

“Not hungry anymore,” Tyson murmured.

Before Annabeth or I could reply, a reptilian voice came from down the corridor, “Ssssix more joined yesssterday.”

Annabeth gestured frantically toward the nearest hiding place—the women’s room—and all three of us ducked inside. I was so freaked out it didn’t even occur to me to be embarrassed.

Something—or more like two somethings—slithered past the bathroom door, making sounds like sandpaper against the carpet.

“Yesss,” a second reptilian voice said. “He drawssss them. Ssssoon we will be sssstrong.”

The things slithered into the cafeteria with a cold hissing that might have been snake laughter.

Annabeth looked at me. “We have to get out of here.”

“You think I want to be in the girls’ restroom?”

“I mean the ship, Percy! We have to get off the ship.”

“Smells bad,” Tyson agreed. “And dogs eat all the eggs. Annabeth is right. We must leave the restroom and ship.”

I shuddered. If Annabeth and Tyson were actually agreeing about something, I figured I’d better listen.

Then I heard another voice outside—one that chilled me worse than any monster’s.

“—only a matter of time. Don’t push me, Agrius!”

It was Luke, beyond a doubt. I could never forget his voice.

“I’m not pushing you!” another guy growled. His voice was deeper and even angrier than Luke’s. “I’m just saying, if this gamble doesn’t pay off—”

“It’ll pay off,” Luke snapped. “They’ll take the bait. Now, come, we’ve got to get to the admiralty suite and check on the casket.”

Their voices receded down the corridor.

Tyson whimpered. “Leave now?”

Annabeth and I exchanged looks and came to a silent agreement.

“We can’t,” I told Tyson.

“We have to find out what Luke is up to,” Annabeth agreed. “And if possible, we’re going to beat him up, bind him in chains, and drag him to Mount Olympus.”

Chapter Nine: I Have The Worst Family Reunion Ever

Annabeth volunteered to go alone since she had the cap of invisibility, but I convinced her it was too dangerous. Either we all went together, or nobody went.

“Nobody!” Tyson voted. “Please?”

But in the end he came along, nervously chewing on his huge fingernails. We stopped at our cabin long enough to gather our stuff. We figured whatever happened, we would not be staying another night aboard the zombie cruise ship, even if they did have million-dollar bingo. I made sure Riptide was in my pocket and the vitamins and thermos from Hermes were at the top of my bag. I didn’t want Tyson to carry everything, but he insisted, and Annabeth told me not to worry about it.

Tyson could carry three full duffel bags over his shoulder as easily as I could carry a backpack.

We sneaked through the corridors, following the ship’s YOU ARE HERE signs toward the admiralty suite. Annabeth scouted ahead invisibly. We hid whenever someone passed by, but most of the people we saw were just glassy-eyed zombie passengers.