My last view of her was sitting in the shotgun seat of the Prius, her arms crossed, watching as Blackjack circled higher and higher, carrying Beckendorf and me into the sky. I wondered what Rachel wanted to talk to me about, and whether I'd live long enough to find out.

"So," Beckendorf said, "I'm guessing you don't want me to mention that little scene to Annabeth."

"Oh, gods," I muttered. "Don't even think about it."

Beckendorf chuckled, and together we soared out over the Atlantic.

It was almost dark by the time we spotted our target. The Princess Andromeda glowed on the horizon—a huge cruise ship lit up yellow and white. From a distance, you'd think it was just a party ship, not the headquarters for the Titan lord. Then as you got closer, you might notice the giant figurehead—a dark-haired maiden in a Greek chiton, wrapped m chains with a look of horror on her face, as if she could smell the stench of all the monsters she was being forced to carry.

Seeing the ship again twisted my gut into knots. I'd almost died twice on the Princess Andromeda. Now it was heading straight for New York.

"You know what to do?" Beckendorf yelled over the wind.

I nodded. We'd done dry runs at the dockyards in New Jersey, using abandoned ships as our targets. I knew how little time we would have. But I also knew this was our best chance to end Kronos's invasion before it ever started.

"Blackjack," I said, "set us down on the lowest stern deck."

Gotcha, boss, he said. Man, I hate seeing that boat.

Three years ago, Blackjack had been enslaved on the Princess Andromeda until he'd escaped with a little help from my friends and me. I figured he'd rather have his mane braided like My Little Pony than be back here again.

"Don't wait for us," I told him.

But, boss—

"Trust me," I said. "We'll get out by ourselves."

Blackjack folded his wings and plummeted toward the boat like a black comet. The wind whistled in my ears. I saw monsters patrolling the upper decks of the ship—dracaenae snake-women, hellhounds, giants, and the humanoid seal-demons known as telkhines—but we zipped by so fast, none of them raised the alarm. We shot down the stern of the boat, and Blackjack spread his wings, lightly coming to a landing on the lowest deck. I climbed off, feeling queasy.

Good luck, boss, Blackjack said. Don't let 'em turn you into horse meat!

With that, my old friend flew off into the night. I took my pen out of my pocket and uncapped it, and Riptide sprang to full size—three feet of deadly Celestial bronze glowing in the dusk.

Beckendorf pulled a piece of paper out of his pocket. I thought it was a map or something. Then I realized it was a photograph. He stared at it in the dim light—the smiling face of Silena Beauregard, daughter of Aphrodite. They'd started going out last summer, after years of the rest of us saying, "Duh, you guys like each other!" Even with all the dangerous missions, Beckendorf had been happier this summer than I'd ever seen him.

"We'll make it back to camp," I promised.

For a second I saw worry in his eyes. Then he put on his old confident smile.

"You bet," he said. "Let's go blow Kronos back into a million pieces."

Beckendorf led the way. We followed a narrow corridor to the service stairwell, just like we'd practiced, but we froze when we heard noises above us.

"I don't care what your nose says!" snarled a half-human, half-dog voice—a telkhine. "The last time you smelled half-blood, it turned out to be a meat loaf sandwich!"

"Meat loaf sandwiches are good!" a second voice snarled. "But this is half-blood scent, I swear. They are on board!"

"Bah, your brain isn't on board!"

They continued to argue, and Beckendorf pointed downstairs. We descended as quietly as we could. Two floors down, the voices of the telkhines started to fade.

Finally we came to a metal hatch. Beckendorf mouthed the words "engine room."

It was locked, but Beckendorf pulled some chain cutters out of his bag and split the bolt like it was made of butter.

Inside, a row of yellow turbines the size of grain silos churned and hummed. Pressure gauges and computer terminals lined the opposite wall. A telkhine was hunched over a console, but he was so involved with his work, he didn't notice us. He was about five feet tall, with slick black seal fur and stubby little feet. He had the head of a Doberman, but his clawed hands were almost human. He growled and muttered as he tapped on his keyboard. Maybe he was messaging his friends on uglyface.com.

I stepped forward, and he tensed, probably smelling something was wrong. He leaped sideways toward a big red alarm button, but I blocked his path. He hissed and lunged at me, but one slice of Riptide, and he exploded into dust.

"One down," Beckendorf said. "About five thousand to go." He tossed me a jar of thick green liquid—Greek fire, one of the most dangerous magical substances in the world. Then he threw me another essential tool of demigod heroes—duct tape.

"Slap that one on the console," he said. "I'll get the turbines."

We went to work. The room was hot and humid, and in no time we were drenched m sweat.

The boat kept chugging along. Being the son of Poseidon and all, I have perfect bearings at sea. Don't ask me how, but I could tell we were at 40.19° North, 71.90° West, making eighteen knots, which meant the ship would arrive in New York Harbor by dawn. This would be our only chance to stop it.

I had just attached a second jar of Greek fire to the control panels when I heard the pounding of feet on metal steps—so many creatures coming down the stairwell I could hear them over the engines. Not a good sign.

I locked eyes with Beckendorf. "How much longer?"

"Too long." He tapped his watch, which was our remote control detonator. "I still have to wire the receiver and prime the charges. Ten more minutes at least."

Judging from the sound of the footsteps, we had about ten seconds.

"I'll distract them," I said. "Meet you at the rendezvous point."

"Percy—"

"Wish me luck."

He looked like he wanted to argue. The whole idea had been to get in and out without being spotted. But we were going to have to improvise.

"Good luck," he said.

I charged out the door.

A half dozen telkhines were tromping down the stairs. I cut through them with Riptide faster than they could yelp. I kept climbing—past another telkhine, who was so startled he dropped his Lil' Demons lunch box. I left him alive—partly because his lunch box was cool, partly so he could raise the alarm and hopefully get his friends to follow me rather than head toward the engine room.

I burst through a door onto deck six and kept running. I'm sure the carpeted hall had once been very plush, but over the last three years of monster occupation the wallpaper, carpet, and stateroom doors had been clawed up and slimed so it looked like the inside of a dragon's throat (and yes, unfortunately, I speak from experience).

Back on my first visit to the Princess Andromeda, my old enemy Luke had kept some dazed tourists on board for show, shrouded in Mist so they didn't realize they were on a monster-infested ship. Now I didn't see any sign of tourists. I hated to think what had happened to them, but I kind of doubted they'd been allowed to go home with their bingo winnings.

I reached the promenade, a big shopping mall that took up the whole middle of the ship, and I stopped cold. In the middle of the courtyard stood a fountain. And in the fountain squatted a giant crab.

I'm not talking "giant" like $7.99 all-you-can-eat Alaskan king crab. I'm talking giant like bigger than the fountain. The monster rose ten feet out of the water. Its shell was mottled blue and green, its pincers longer than my body.