THEY WERE CROSSING THE POTOMAC when they spotted the helicopter. It was a sleek, black military model just like the one they'd seen at Westover Hall. And it was coming straight toward them.

"They know the van," Percy said. "We have to ditch it."

Zoe swerved into the fast lane. The helicopter was gaining.

"Maybe the military will shoot it down," Grover said hopefully.

"The military probably thinks it's one of theirs," Percy replied, "How can the General use mortals, anyway?"

"Mercenaries," Zoe answered bitterly. "It is distasteful, but many mortals will fight for any cause as long as they are paid."

"But don't these mortals see who they're working for?" Percy asked. "Don't they notice all the monsters around them?"

Zoe shook her head. "I do not know how much they see through the Mist. I doubt it would matter to them if they knew the truth. Sometimes mortals can be more horrible than monsters."

The helicopter kept coming, making a lot better time than they were through D.C. traffic.

Thalia closed her eyes and prayed hard. "Hey, Dad. A lightning bolt would be nice about now. Please?"

But the sky stayed gray and snowy. No sign of a helpful thunderstorm.

"There!" Bianca pointed, "That parking lot!"

"We'll be trapped," Zoe said.

"Trust me," Bianca replied,

Zoe shot across two lanes of traffic and into a mall parking lot on the south bank of the river. They left the van and followed Bianca down some steps.

"Subway entrance," Bianca stated. "Let's go south. Alexandria."

"Anything," Thalia agreed.

They bought tickets and got through the turnstiles, looking behind them for any signs of pursuit. A few minutes later they were safely aboard a southbound train, riding away from D.C. As their train came above ground, the group could see the helicopter circling the parking lot, but it didn't come after them.

Grover let out a sigh. "Nice job, Bianca, thinking of the subway."

Bianca looked pleased. "Yeah, well. I saw that station when Nico and I came through last summer. I remember being really surprised to see it, because it wasn't here when we used to live in D.C."

Grover frowned. "New? But that station looked really old."

"I guess," Bianca said. "But trust me, when we lived here as little kids, there was no subway."

Thalia sat forward. "Wait a minute. No subway at all?"

Bianca nodded.

Selena stared at the girl curiously. She knew nothing about D.C., but Selena didn't see how their whole subway system could be less than twelve years old. She guessed everyone else was thinking the same thing, because they looked pretty confused.

"Bianca," Zoe said. "How long ago..." Her voice faltered. The sound of the helicopter was getting louder again.

"We need to change trains," Percy stated. "Next station."

Over the next half hour, all they thought about was getting away safely. They changed trains twice. Selena had no idea where they were going, but after a while they lost the helicopter.

Unfortunately, when the six of them finally got off the train they found ourselves at the end of the line, in an industrial area with nothing but warehouses and railway tracks. And snow. Lots of snow. It seemed much colder here. 

They wandered through the railway yard, thinking there might be another passenger train somewhere, but there were just rows and rows of freight cars, most of which were covered in snow, like they hadn't moved in years.

A homeless guy was standing at a trash-can fire. They must've looked pretty pathetic, because he gave us a toothless grin and said, "Y'all need to get warmed up? Come on over!'

They huddled around his fire, Thalia's teeth were chattering. She said, "Well this is g-g-g-great."

"My hooves are frozen," Grover complained.

"Feet," Percy corrected, for the sake of the homeless guy.

"Maybe we should contact camp," Bianca suggested, "Chiron—"

"No," Zoe interrupted, "They cannot help us anymore. We must finish this quest ourselves."

Selena gazed miserably around the rail yard. Somewhere, far to the west, Annabeth was in danger. Artemis was in chains. A doomsday monster was on the loose. And they were stuck on the outskirts of D.C., sharing a homeless persons fire.

"You know," the homeless man said, "you're never completely without friends." His face was grimy and his beard tangled, but his expression seemed kindly. "You kids need a train going west?"

"Yes, sir," Percy answered, "You know of any?"

He pointed one greasy hand.

Suddenly, they noticed a freight train, gleaming and free of snow. It was one of those automobile-carrier trains, with steel mesh curtains and a triple-deck of cars inside. The side of the freight train said SUN WEST LINE.

"That's... convenient," Thalia said. "Thanks, uh..." She turned to the homeless guy, but he was gone. The trash can in front of them was cold and empty, as if he'd taken the flames with him.

An hour later, they were rumbling west. There was no problem about who would drive now, because they all got their own luxury car. 

Zoe and Bianca were crashed out in a Lexus on the top deck. 

Grover was playing race car driver behind the wheel of a Lamborghini.

 Thalia had hot-wired the radio in a black Mercedes SLK so she could pick up the alt-rock stations from D.C.

And Selena sat in the front seat of an Audi A8, playing with her dagger. She was afraid to fall asleep, afraid of what she might see when she closes her eyes.

"Ah, prophecies. They can be a real downer, can't they?" Selena turned to see Apollo sitting in the passenger seat.

"Come to help us out, oh mighty sun God?" Selena asked, setting down her dagger in her lap.

"More like give some friendly advice." He replied,

"Dying for dummies?"

He gave her one of his blinding smiles, "Funny, kid. It seems like you and your friends are scared of your dreams."

"Yeah, well, every time I try to sleep I see my death, so, I'm sorry if I don't want to sleep right now." Selena snapped.

"Meow, kitty cat." Apollo grinned, "Someone's feisty. I just wanna help, kid."

"I don't need help." Selena replied,

"Nonsense. Maybe you need some sleep." He held up his hand and Selena shook her head,

"Please, don't."

"Too late." He snapped his fingers and Selena instantly fell asleep.

She was in a dark cave. The walls glittered with crystals—red, green, and blue. In the strange light, beautiful plants grew—giant orchids, star-shaped flowers, vines bursting with orange and purple berries that crept among the crystals. The cave floor was covered with green moss. Overhead, the ceiling was higher than a cathedral, sparkling like a galaxy of stars. In the center of the cave stood a Roman-style bed, gilded wood shaped like a curly U, with velvet cushions. Animals lounged around it—but they were animals that shouldn't have been alive. There was a dodo bird, something that looked like a cross between a wolf and a tiger, a huge rodent like the mother of all guinea p, gs, and roaming behind the bed, picking berries with its trunk, was a wooly mammoth.

Next to her were her friends. Percy, Annabeth, Tyson and Grover. But after a moment, they faded away. 

"Percy? Annabeth?" Selena turned around, looking for them, "Guys?!"

Then she spotted him.

On the bed lay an old satyr. He watched them as they approached, his eyes as blue as the sky. His curly hair was white and so was his pointed beard. Even the goat fur on his legs was frosted with gray. His horns were enormous— glossy brown and curved. There was no way he could've hidden those under a hat the way Grover did. Around his neck hung a set of reed pipes.

"Are you who I think you are?" Selena asked, kneeling before him.

The satyr gave her a small smile, "The unloved daughter, Selena Madison."

"That's a bit harsh." Selena stated,

"You are strong, child. Especially when excepting your fate. But it's okay to be afraid. Your memory will live on in the hearts of those around you."