But that didn’t make her fear easier to deal with. Once, she’d almost killed Connor Stoll at camp for putting a tarantula in her bunk. Years later, she’d had a panic attack at a water park in Denver, when Percy and she were assaulted by mechanical spiders. And the past few weeks, Annabeth had dreamed of spiders almost every night—crawling over her, suffocating her, wrapping her in webs.

Now, standing in the barracks at Fort Sumter, she was surrounded. Her nightmares had come true.

A sleepy voice murmured in her head: Soon, my dear. You will meet the weaver soon.

“Gaea?” Annabeth murmured. She feared the answer, but she asked: “Who—who is the weaver?”

The spiders became excited, swarming over the walls, swirling around Annabeth’s feet like a glistening black whirlpool. Only the hope that it might be an illusion kept Annabeth from passing out from fear.

I hope you survive, child, the woman’s voice said. I would prefer you as my sacrifice. But we must let the weaver take her revenge…

Gaea’s voice faded. On the far wall, in the center of the spider swarm, a red symbol blazed to life: the figure of an owl like the one on the silver drachma, staring straight at Annabeth. Then, just as in her nightmares, the Mark of Athena burned across the walls, incinerating the spiders until the room was empty except for the smell of sickly sweet ashes.

Go, said a new voice—Annabeth’s mother. Avenge me. Follow the Mark.

The blazing symbol of the owl faded. The garrison door burst open. Annabeth stood stunned in the middle of the room, unsure whether she’d seen something real, or just a vision.

An explosion shook the building. Annabeth remembered that her friends were in danger. She’d stayed here much too long.

She forced herself to move. Still trembling, she stumbled outside. The ocean air helped clear her mind. She gazed across the courtyard—past the panicked tourists and fighting demigods—to the edge of the battlements, where a large mortar pointed out to sea.

It might have been Annabeth’s imagination, but the old artillery piece seemed to be glowing red. She dashed toward it. An eagle swooped at her, but she ducked and kept running. Nothing could possibly scare her as much as those spiders.

Roman demigods had formed ranks and were advancing toward the Argo II, but a miniature storm had gathered over their heads. Though the day was clear all around them, thunder rumbled, and lightning flashed above the Romans. Rain and wind pushed them back.

Annabeth didn’t stop to think about it.

She reached the mortar and put her hand on the muzzle. On the plug that blocked the opening, the Mark of Athena began to glow—the red outline of an owl.

“In the mortar,” she said. “Of course.”

She pried at the plug with her fingers. No luck. Cursing, she drew her dagger. As soon as the Celestial bronze touched the plug, the plug shrank and loosened. Annabeth pulled it off and stuck her hand inside the cannon.

Her fingers touched something cold, smooth, and metal. She pulled out a small disk of bronze the size of a tea saucer, etched with delicate letters and illustrations. She decided to examine it later. She thrust it in her pack and turned.

“Rushing off?” Reyna asked.

The praetor stood ten feet away, in full battle armor, holding a golden javelin. Her two metal greyhounds growled at her side.

Annabeth scanned the area. They were more or less alone. Most of the combat had moved toward the docks. Hopefully her friends had all made it on board, but they’d have to set sail immediately or risk being overrun. Annabeth had to hurry.

“Reyna,” she said, “what happened at Camp Jupiter was Gaea’s fault. Eidolons, possessing spirits—”

“Save your explanations,” Reyna said. “You’ll need them for the trial.”

The dogs snarled and inched forward. This time, it didn’t seem to matter to them that Annabeth was telling the truth. She tried to think of an escape plan. She doubted she could take Reyna in one-on-one combat. With those metal dogs, she stood no chance at all.

“If you let Gaea drive our camps apart,” Annabeth said, “the giants have already won. They’ll destroy the Romans, the Greeks, the gods, the whole mortal world.”

“Don’t you think I know that?” Reyna’s voice was as hard as iron. “What choice have you left me? Octavian smells blood. He’s whipped the legion into a frenzy, and I can’t stop it. Surrender to me. I’ll bring you back to New Rome for trial. It won’t be fair. You’ll be painfully executed. But it may be enough to stop further violence. Octavian won’t be satisfied, of course, but I think I can convince the others to stand down.”

“It wasn’t me!”

“It doesn’t matter!” Reyna snapped. “Someone must pay for what happened. Let it be you. It’s the better option.”

Annabeth’s skin crawled. “Better than what?”

“Use that wisdom of yours,” Reyna said. “If you escape today, we won’t follow. I told you—not even a madman would cross the sea to the ancient lands. If Octavian can’t have vengeance on your ship, he’ll turn his attention to Camp Half-Blood. The legion will march on your territory. We will raze it and salt the earth.”

Kill the Romans, she heard her mother urging. They can never be your allies.

Annabeth wanted to sob. Camp Half-Blood was the only real home she’d ever known, and in a bid for friendship, she had told Reyna exactly where to find it. She couldn’t leave it at the mercy of the Romans and travel halfway around the world.

But their quest, and everything she’d suffered to get Percy back…if she didn’t go to the ancient lands, it would all mean nothing. Besides, the Mark of Athena didn’t have to lead to revenge.

If I could find the route, her mother had said, the way home…

How will you use your reward? Aphrodite had asked. For war or peace?

There was an answer. The Mark of Athena could lead her there—if she survived.

“I’m going,” she told Reyna. “I’m following the Mark of Athena to Rome.”

The praetor shook her head. “You have no idea what awaits you.”

“Yes, I do,” Annabeth said. “This grudge between our camps…I can fix it.”

“Our grudge is thousands of years old. How can one person fix it?”

Annabeth wished she could give a convincing answer, show Reyna a 3-D diagram or a brilliant schematic, but she couldn’t. She just knew she had to try. She remembered that lost look on her mother’s face: I must return home.

“The quest has to succeed,” she said. “You can try to stop me, in which case we’ll have to fight to the death. Or you can let me go, and I’ll try to save both our camps. If you must march on Camp Half-Blood, at least try to delay. Slow Octavian down.”

Reyna’s eyes narrowed. “One daughter of a war goddess to another, I respect your boldness. But if you leave now, you doom your camp to destruction.”

“Don’t underestimate Camp Half-Blood,” Annabeth warned.

“You’ve never seen the legion at war,” Reyna countered.

Over by the docks, a familiar voice shrieked over the wind: “Kill them! Kill them all!”

Octavian had survived his swim in the harbor. He crouched behind his guards, screaming encouragement at the other Roman demigods as they struggled toward the ship, holding up their shields as if that would deflect the storm raging all around them.

On the deck of the Argo II, Percy and Jason stood together, their swords crossed. Annabeth got a tingle down her spine as she realized the boys were working as one, summoning the sky and the sea to do their bidding. Water and wind churned together. Waves heaved against the ramparts and lightning flashed. Giant eagles were knocked out of the sky. Wreckage of the flying chariot burned in the water, and Coach Hedge swung a mounted crossbow, taking potshots at the Roman birds as they flew overhead.

“You see?” Reyna said bitterly. “The spear is thrown. Our people are at war.”

“Not if I succeed,” Annabeth said.

Reyna’s expression looked the same as it had at Camp Jupiter when she realized Jason had found another girl. The praetor was too alone, too bitter and betrayed to believe anything could go right for her ever again. Annabeth waited for her to attack.

Instead, Reyna flicked her hand. The metal dogs backed away. “Annabeth Chase,” she said, “when we meet again, we will be enemies on the field of battle.”

The praetor turned and walked across the ramparts, her greyhounds behind her.

Annabeth feared it might be some sort of trick, but she had no time to wonder. She ran for the ship.

The winds that battered the Romans didn’t seem to affect her.

Annabeth sprinted through their lines. Octavian yelled, “Stop her!”

A spear flew past her ear. The Argo II was already pulling away from the dock. Piper was at the gangplank, her hand outstretched.

Annabeth leaped and grabbed Piper’s hand. The gangplank fell into the sea, and the two girls tumbled onto the deck.

“Go!” Annabeth screamed. “Go, go, go!”

The engines rumbled beneath her. The oars churned. Jason changed the course of the wind, and Percy called up a massive wave, which lifted the ship higher than the fort’s walls and pushed it out to sea. By the time the Argo II reached top speed, Fort Sumter was only a blot in the distance, and they were racing across the waves toward the ancient lands.

Chapter 21

After raiding a museum full of Confederate ghosts, Leo didn’t think his day could get any worse. He was wrong.

They hadn’t found anything in the Civil War sub or elsewhere in the museum; just a few elderly tourists, a dozing security guard, and—when they tried to inspect the artifacts—a whole battalion of glowing zombie dudes in gray uniforms.

The idea that Frank should be able to control the spirits? Yeah…that pretty much failed. By the time Piper sent her Iris-message warning them about the Roman attack, they were already halfway back to the ship, having been chased through downtown Charleston by a pack of angry dead Confederates.

Then—oh, boy!—Leo got to hitch a ride with Frank the Friendly Eagle so they could fight a bunch of Romans. Rumor must’ve gotten around that Leo was the one who had fired on their little city, because those Romans seemed especially anxious to kill him.

But wait! There was more! Coach Hedge shot them out of the sky; Frank dropped him (that was no accident); and they crash-landed in Fort Sumter.

Now, as the Argo II raced across the waves, Leo had to use all his skill just to keep the ship in one piece. Percy and Jason were a little too good at cooking up massive storms.

At one point, Annabeth stood next to him, yelling against the roar of the wind: “Percy says he talked to a Nereid in Charleston Harbor!”

“Good for him!” Leo yelled back.

“The Nereid said we should seek help from Chiron’s brothers.”

“What does that mean? The Party Ponies?” Leo had never met Chiron’s crazy centaur relatives, but he’d heard rumors of Nerf sword-fights, root beer–chugging contests, and Super Soakers filled with pressurized whipped cream.