"You..." Annabeth said in amazement. "And Hylla is queen of the Amazons? How did you two-?"

"Long story," Reyna said. "But I remember you well. You were brave. I'd never seen anyone refuse Circe's hospitality, much less outwit her. It's no wonder Percy cares for you."

Her voice was wistful. Annabeth thought it might be safer not to respond.

They reached the top of the hill, where a terrace overlooked the entire valley.

"This is my favorite spot," Reyna said. "The Garden of Bacchus."

Grapevine trellises made a canopy overhead. Bees buzzed through honeysuckle and jasmine, which filled the afternoon air with a dizzying mix of perfumes. In the middle of the terrace stood a statue of Bacchus in a sort of ballet position, wearing nothing but a loincloth, his cheeks puffed out and lips pursed, spouting water into a fountain.

Despite her worries, Annabeth almost laughed. She knew the god in his Greek form, Dionysus-or Mr. D, as they called him back at Camp Half-Blood. Seeing their cranky old camp director immortalized in stone, wearing a diaper and spewing water from his mouth, made her feel a little better.

Reyna stopped at the edge of the terrace. The view was worth the climb. The whole city spread out below them like a 3-D mosaic. To the south, beyond the lake, a cluster of temples perched on a hill. To the north, an aqueduct marched toward the Berkeley Hills. Work crews were repairing a broken section, probably damaged in the recent battle.

"I wanted to hear it from you," Reyna said.

Annabeth turned. "Hear what from me?"

"The truth," Reyna said. "Convince me that I'm not making a mistake by trusting you. Tell me about yourself. Tell me about Camp Half-Blood. Your friend Piper has sorcery in her words. I spent enough time with Circe to know charmspeak when I hear it. I can't trust what she says. And Jason...well, he has changed. He seems distant, no longer quite Roman."

The hurt in her voice was as sharp as broken glass. Annabeth wondered if she had sounded that way, all the months she'd spent searching for Percy. At least she'd found her boyfriend. Reyna had no one. She was responsible for running an entire camp all by herself. Annabeth could sense that Reyna wanted Jason to love her. But he had disappeared, only to come back with a new girlfriend. Meanwhile, Percy had risen to praetor, but he had rebuffed Reyna too. Now Annabeth had come to take him away. Reyna would be left alone again, shouldering a job meant for two people.

When Annabeth had arrived at Camp Jupiter, she'd been prepared to negotiate with Reyna or even fight her if needed. She hadn't been prepared to feel sorry for her.

She kept that feeling hidden. Reyna didn't strike her as someone who would appreciate pity.

Instead, she told Reyna about her own life. She talked about her dad and stepmom and her two stepbrothers in San Francisco, and how she had felt like an outsider in her own family. She talked about how she had run away when she was only seven, finding her friends Luke and Thalia and making her way to Camp Half-Blood on Long Island. She described the camp and her years growing up there. She talked about meeting Percy and the adventures they'd had together.

Reyna was a good listener.

Annabeth was tempted to tell her about more recent problems: her fight with her mom, the gift of the silver coin, and the nightmares she'd been having-about an old fear so paralyzing, she'd almost decided that she couldn't go on this quest. But she couldn't bring herself to open up quite that much.

When Annabeth was done talking, Reyna gazed over New Rome. Her metal greyhounds sniffed around the garden, snapping at bees in the honeysuckle. Finally Reyna pointed to the cluster of temples on the distant hill.

"The small red building," she said, "there on the northern side? That's the temple of my mother, Bellona." Reyna turned toward Annabeth. "Unlike your mother, Bellona has no Greek equivalent. She is fully, truly Roman. She's the goddess of protecting the homeland."

Annabeth said nothing. She knew very little about the Roman goddess. She wished she had studied up, but Latin never came as easily to her as Greek. Down below, the hull of the Argo II gleamed as it floated over the forum, like some massive bronze party balloon.

"When the Romans go to war," Reyna continued, "we first visit the Temple of Bellona. Inside is a symbolic patch of ground that represents enemy soil. We throw a spear into that ground, indicating that we are now at war. You see, Romans have always believed that offense is the best defense. In ancient times, whenever our ancestors felt threatened by their neighbors, they would invade to protect themselves."

"They conquered everyone around them," Annabeth said. "Carthage, the Gauls-"

"And the Greeks." Reyna let that comment hang. "My point, Annabeth, is that it isn't Rome's nature to cooperate with other powers. Every time Greek and Roman demigods have met, we've fought. Conflicts between our two sides have started some of the most horrible wars in human history-especially civil wars."

"It doesn't have to be that way," Annabeth said. "We've got to work together, or Gaea will destroy us both."

"I agree," Reyna said. "But is cooperation possible? What if Juno's plan is flawed? Even goddesses can make mistakes."

Annabeth waited for Reyna to get struck by lightning or turned into a peacock. Nothing happened.

Unfortunately, Annabeth shared Reyna's doubts. Hera did make mistakes. Annabeth had had nothing but trouble from that overbearing goddess, and she'd never forgive Hera for taking Percy away, even if it was for a noble cause.

"I don't trust the goddess," Annabeth admitted. "But I do trust my friends. This isn't a trick, Reyna. We can work together."

Reyna finished her cup of chocolate. She set the cup on the terrace railing and gazed over the valley as if imagining battle lines.

"I believe you mean it," she said. "But if you go to the ancient lands, especially Rome itself, there is something you should know about your mother."

Annabeth's shoulders tensed. "My-my mother?"

"When I lived on Circe's island," Reyna said, "we had many visitors. Once, perhaps a year before you and Percy arrived, a young man washed ashore. He was half mad from thirst and heat. He'd been drifting at sea for days. His words didn't make much sense, but he said he was a son of Athena."

Reyna paused as if waiting for a reaction. Annabeth had no idea who the boy might have been. She wasn't aware of any other Athena kids who'd gone on a quest in the Sea of Monsters, but still she felt a sense of dread. The light filtering through the grapevines made shadows writhe across the ground like a swarm of bugs.

"What happened to this demigod?" she asked.

Reyna waved her hand as if the question was trivial. "Circe turned him into a guinea pig, of course. He made quite a crazy little rodent. But before that, he kept raving about his failed quest. He claimed that he'd gone to Rome, following the Mark of Athena."

Annabeth grabbed the railing to keep her balance.

"Yes," Reyna said, seeing her discomfort. "He kept muttering about wisdom's child, the Mark of Athena, and the giants' bane standing pale and gold. The same lines Ella was just reciting. But you say that you've never heard them before today?"

"Not-not the way Ella said them." Annabeth's voice was weak. She wasn't lying. She'd never heard that prophecy, but her mother had charged her with following the Mark of Athena; and as she thought about the coin in her pocket, a horrible suspicion began taking root in her mind. She remembered her mother's scathing words. She thought about the strange nightmares she'd been having lately. "Did this demigod-did he explain his quest?"

Reyna shook her head. "At the time, I had no idea what he was talking about. Much later, when I became praetor of Camp Jupiter, I began to suspect."

"Suspect...what?"

"There is an old legend that the praetors of Camp Jupiter have passed down through the centuries. If it's true, it may explain why our two groups of demigods have never been able to work together. It may be the cause of our animosity. Until this old score is finally settled, so the legend goes, Romans and Greeks will never be at peace. And the legend centers on Athena-"

A shrill sound pierced the air. Light flashed in the corner of Annabeth's eye.

She turned in time to see an explosion blast a new crater in the forum. A burning couch tumbled through the air. Demigods scattered in panic.

"Giants?" Annabeth reached for her dagger, which of course wasn't there. "I thought their army was defeated!"

"It isn't the giants." Reyna's eyes seethed with rage. "You've betrayed our trust."

"What? No!"

As soon as she said it, the Argo II launched a second volley. Its port ballista fired a massive spear wreathed in Greek fire, which sailed straight through the broken dome of the Senate House and exploded inside, lighting up the building like a jack-o'-lantern. If anyone had been in there...

"Gods, no." A wave of nausea almost made Annabeth's knees buckle. "Reyna, it isn't possible. We'd never do this!"

The metal dogs ran to their mistress's side. They snarled at Annabeth but paced uncertainly, as if reluctant to attack.

"You're telling the truth," Reyna judged. "Perhaps you were not aware of this treachery, but someone must pay."

Down in the forum, chaos was spreading. Crowds were pushing and shoving. Fistfights were breaking out.

"Bloodshed," Reyna said.

"We have to stop it!"

Annabeth had a horrible feeling this might be the last time Reyna and she ever acted in agreement, but together they ran down the hill.

If weapons had been allowed in the city, Annabeth's friends would have already been dead. The Roman demigods in the forum had coalesced into an angry mob. Some threw plates, food, and rocks at the Argo II, which was pointless, as most of the stuff fell back into the crowd.

Several dozen Romans had surrounded Piper and Jason, who were trying to calm them without much luck. Piper's charmspeak was useless against so many screaming, angry demigods. Jason's forehead was bleeding. His purple cloak had been ripped to shreds. He kept pleading, "I'm on your side!" but his orange Camp Half-Blood T-shirt didn't help matters-nor did the warship overhead, firing flaming spears into New Rome. One landed nearby and blasted a toga shop to rubble.

"Pluto's pauldrons," Reyna cursed. "Look."

Armed legionnaires were hurrying toward the forum. Two artillery crews had set up catapults just outside the Pomerian Line and were preparing to fire at the Argo II.

"That'll just make things worse," Annabeth said.

"I hate my job," Reyna growled. She rushed off toward the legionnaires, her dogs at her side.

Percy, Annabeth thought, scanning the forum desperately. Where are you?

Two Romans tried to grab her. She ducked past them, plunging into the crowd. As if the angry Romans, burning couches, and exploding buildings weren't confusing enough, hundreds of purple ghosts drifted through the forum, passing straight through the demigods' bodies and wailing incoherently. The fauns had also taken advantage of the chaos. They swarmed the dining tables, grabbing food, plates, and cups. One trotted by Annabeth with his arms full of tacos and an entire pineapple between his teeth.

A statue of Terminus exploded into being, right in front of Annabeth. He yelled at her in Latin, no doubt calling her a liar and a rule breaker; but she pushed the statue over and kept running.

Finally she spotted Percy. He and his friends, Hazel and Frank, were standing in the middle of a fountain as Percy repelled the angry Romans with blasts of water. Percy's toga was in tatters, but he looked unhurt.

Annabeth called to him as another explosion rocked the forum. This time the flash of light was directly overhead. One of the Roman catapults had fired, and the Argo II groaned and tilted sideways, flames bubbling over its bronze-plated hull.

Annabeth noticed a figure clinging desperately to the rope ladder, trying to climb down. It was Octavian, his robes steaming and his face black with soot.

Over by the fountain, Percy blasted the Roman mob with more water. Annabeth ran toward him, ducking a Roman fist and a flying plate of sandwiches.

"Annabeth!" Percy called. "What-?"

"I don't know!" she yelled.

"I'll tell you what!" cried a voice from above. Octavian had reached the bottom of the ladder. "The Greeks have fired on us! Your boy Leo has trained his weapons on Rome!"

Annabeth's chest filled with liquid hydrogen. She felt like she might shatter into a million frozen pieces.

"You're lying," she said. "Leo would never-"

"I was just there!" Octavian shrieked. "I saw it with my own eyes!"

The Argo II returned fire. Legionnaires in the field scattered as one of their catapults was blasted to splinters.

"You see?" Octavian screamed. "Romans, kill the invaders!"

Annabeth growled in frustration. There was no time for anyone to figure out the truth. The crew from Camp Half-Blood was outnumbered a hundred to one, and even if Octavian had managed to stage some sort of trick (which she thought likely), they'd never be able to convince the Romans before they were overrun and killed.

"We have to leave," she told Percy. "Now."

He nodded grimly. "Hazel, Frank, you've got to make a choice. Are you coming?"

Hazel looked terrified, but she donned her cavalry helmet. "Of course we are. But you'll never make it to the ship unless we buy you some time."

"How?" Annabeth asked.

Hazel whistled. Instantly a blur of beige shot across the forum. A majestic horse materialized next to the fountain. He reared, whinnying and scattering the mob. Hazel climbed on his back like she'd been born to ride. Strapped to the horse's saddle was a Roman cavalry sword.

Hazel unsheathed her golden blade. "Send me an Iris-message when you're safely away, and we'll rendezvous," she said. "Arion, ride!"

The horse zipped through the crowd with incredible speed, pushing back Romans and causing mass panic.

Annabeth felt a glimmer of hope. Maybe they could make it out of here alive. Then, from halfway across the forum, she heard Jason shouting.

"Romans!" he cried. "Please!"

He and Piper were being pelted with plates and stones. Jason tried to shield Piper, but a brick caught him above the eye. He crumpled, and the crowd surged forward.

"Get back!" Piper screamed. Her charmspeak rolled over the mob, making them hesitate, but Annabeth knew the effect wouldn't last. Percy and she couldn't possibly reach them in time to help.

"Frank," Percy said, "it's up to you. Can you help them?"

Annabeth didn't understand how Frank could do that all by himself, but he swallowed nervously.

"Oh, gods," he murmured. "Okay, sure. Just get up the ropes. Now."

Percy and Annabeth lunged for the ladder. Octavian was still clinging to the bottom, but Percy yanked him off and threw him into the mob.

They began to climb as armed legionnaires flooded into the forum. Arrows whistled past Annabeth's head. An explosion almost knocked her off the ladder. Halfway up, she heard a roar below and glanced down.

Romans screamed and scattered as a full-sized dragon charged through the forum-a beast even scarier than the bronze dragon figurehead on the Argo II. It had rough gray skin like a Komodo lizard's and leathery bat wings. Arrows and rocks bounced harmlessly off its hide as it lumbered toward Piper and Jason, grabbed them with its front claws, and vaulted into the air.

"Is that... ?" Annabeth couldn't even put the thought into words.

"Frank," Percy confirmed, a few feet above her. "He has a few special talents."

"Understatement," Annabeth muttered. "Keep climbing!"

Without the dragon and Hazel's horse to distract the archers, they never would have made it up the ladder; but finally they climbed past a row of broken aerial oars and onto the deck. The rigging was on fire. The foresail was ripped down the middle, and the ship listed badly to starboard.

There was no sign of Coach Hedge, but Leo stood amidships, calmly reloading the ballista. Annabeth's gut twisted with horror.

"Leo!" she screamed. "What are you doing?"

"Destroy them..." He faced Annabeth. His eyes were glazed. His movements were like a robot's. "Destroy them all."