The waiter brought fresh-baked bread and cheese, a bottle of sparkling water for Annabeth, and a Coke with ice for me (because I’m a barbarian). We dined on a bunch of stuff I couldn’t even pronounce—but all of it was great. It was almost half an hour before Annabeth got over her shock and spoke.

“This is…incredible.”

“Only the best for you,” I said. “And you thought I forgot.”

“You did forget, Seaweed Brain.” But her smile told me she wasn’t really mad. “Nice save, though. I’m impressed.”

“I have my moments.”

“You certainly do.” She reached across the table and took my hand. Her expression turned serious. “Any idea why Hermes acted so nervous? I got the feeling something bad was happening on Olympus.”

I shook my head. I may not see you for a while, the god had said, almost like he was warning me about something to come.

“Let’s just enjoy tonight,” I said. “Hermes will be teleporting us back at midnight.”

“Time for a walk along the river,” Annabeth suggested. “And Percy…feel free to start planning our two-month anniversary.”

“Oh, gods.” I felt panicky at the thought, but also really good. I’d survived a month as Annabeth’s boyfriend, so I guess I hadn’t screwed things up too badly. In fact, I’d never been happier. If she saw a future for us—if she was still planning to be with me next month, then that was good enough for me.

“How about we go for that walk?” I pulled out the credit card Hermes had tucked in my pocket—a black metal Olympus Express—and set it on the table. “I want to explore Paris with a beautiful girl.”

Interview with George and Martha, Hermes's Snakes

It’s such an honor to speak with you. You’re quite famous, you know.

GEORGE: That’s right, buddy. We are VISs—very important snakes. Without us, Hermes’s staff would be nothing but a boring old branch.

MARTHA: Shhhh…he might hear you. Hermes, if you’re listening, we think you’re wonderful.

GEORGE: Yes, we’re very glad you caught us, Hermes. Please don’t stop feeding us.

What’s it like to work for Hermes?

MARTHA: We work with Hermes, dear. Not for.

GEORGE: Yeah, just because he caught us and made us part of his caduceus doesn’t mean he owns us. We’re his constant companions and he’d be bored without us. And he’d look quite silly without his caduceus, now, wouldn’t he?

What’s the best part of your job?

MARTHA: I like talking with the young demigods. So sweet, those children. It’s sad to see when they turn bad, though.…

GEORGE: That Kronos business was a mess, but let’s not talk about the sad stuff. Let’s talk about the fun stuff, like lasers and traveling the world with Hermes.

Yes, what do you do while Hermes is off delivering packages, acting as a patron to travelers and thieves, and being a messenger of the gods?

GEORGE: Well, it’s not like we’re useless, you know. What, you think we just hang around and sunbathe on the caduceus all day?

MARTHA: George, hush, you’re being rude.

GEORGE: But he should know that we’re quite indispensible.

MARTHA: What George means is that we do a lot for Hermes. First of all, we provide moral support to Hermes, and I’d like to think that our soothing presence helps young demigods when Hermes is delivering so-so news.

GEORGE: We do cooler stuff than that. Hermes can use the caduceus as a cattle prod, a laser, even a cell phone, and when he does, yours truly is the antennae.

MARTHA: And when he delivers packages and customers need to sign their receipts, I—

GEORGE: She’s the pen, I’m the notepad.

MARTHA: George, don’t interrupt.

GEORGE: All I’m saying is that Hermes couldn’t do his job without us!

Phone, notepad, pen—it sounds like you guys wear a lot of hats.

GEORGE: Did you say rats?

MARTHA: No, no, he said hats. Because we do a lot of different things, we wear a lot of different hats.

GEORGE: Rats are delicious.

MARTHA: Not rats with an R, HATS with an—

GEORGE: All this talk about rats is making me hungry. Let’s go get lunch.

Leo Valdez and the Quest for Buford

LEO BLAMED THE WINDEX. He should’ve known better. Now his entire project—two months of work—might literally blow up in his face.

He stormed around Bunker 9, cursing himself for being so stupid, while his friends tried to calm him down.

“It’s okay,” Jason said. “We’re here to help.”

“Just tell us what happened,” Piper urged.

Thank goodness they’d answered his distress call so quickly. Leo couldn’t turn to anyone else. Having his best friends at his side made him feel better, though he wasn’t sure they could stop the disaster.

Jason looked cool and confident as usual—all surfer-dude handsome with his blond hair and sky-blue eyes. The scar on his mouth and the sword at his side gave him a rugged appearance, like he could handle anything.

Piper stood next to him in her jeans and orange camp T-shirt.

Her long brown hair was braided on one side. Her dagger Katoptris gleamed at her belt. Despite the situation, her multicolored eyes sparkled like she was trying to suppress a smile. Now that Jason and she were officially together, Piper looked like that a lot.

Leo took a deep breath. “Okay, guys. This is serious. Buford’s gone. If we don’t get him back, this whole place is going to explode.”

Piper’s eyes lost some of that smiley sparkle. “Explode? Um…okay. Just calm down and tell us who Buford is.”

She probably didn’t do it on purpose, but Piper had this child-of-Aphrodite power called charmspeak that made her voice hard to ignore. Leo felt his muscles relaxing. His mind cleared a little.

“Fine,” he said. “Come here.”

He led them across the hangar floor, carefully skirting some of his more dangerous projects. In his two months at Camp Half-Blood, Leo had spent most of his time at Bunker 9. After all, he’d rediscovered the secret workshop. Now it was like a second home to him. But he knew his friends still felt uncomfortable here.

He couldn’t blame them. Built into the side of a limestone cliff deep in the woods, the bunker was part weapons depot, part machine shop, and part underground safe house, with a little bit of Area 51–style craziness thrown in for good measure. Rows of workbenches stretched into the darkness. Tool cabinets, storage closets, cages full of welding equipment, and stacks of construction material made a labyrinth of aisles so vast, Leo figured he’d only explored about ten percent of it so far. Overhead ran a series of catwalks and pneumatic tubes for delivering supplies, plus a high-tech lighting and sound system that Leo was just starting to figure out.

A large magical banner hung over the center of the production floor. Leo had recently discovered how to change the display, like the Times Square JumboTron, so now the banner read: Merry Christmas! All your presents belong to Leo!

He ushered his friends to the central staging area. Decades ago, Leo’s metallic friend Festus the bronze dragon had been created here. Now, Leo was slowly assembling his pride and joy—the Argo II.

At the moment, it didn’t look like much. The keel was laid—a length of Celestial bronze curved like an archer’s bow, two hundred feet from bow to stern. The lowest hull planks had been set in place, forming a shallow bowl held together by scaffolding. Masts lay to one side, ready for positioning. The bronze dragon figurehead—formerly the head of Festus—sat nearby, carefully wrapped in velvet, waiting to be installed in its place of honor.

Most of Leo’s time had been spent in the middle of the ship, at the base of the hull, where he was building the engine that would run the warship.

He climbed the scaffolding and jumped into the hull. Jason and Piper followed.

“See?” Leo said.

Fixed to the keel, the engine apparatus looked like a high-tech jungle gym made from pipes, pistons, bronze gears, magical disks, steam vents, electric wires, and a million other magical and mechanical pieces. Leo slid inside and pointed out the combustion chamber.

It was a thing of beauty, a bronze sphere the size of a basketball, its surface bristling with glass cylinders so it looked like a mechanical starburst. Gold wires ran from the ends of the cylinders, connecting to various parts of the engine. Each cylinder was filled with a different magical and highly dangerous substance. The central sphere had a digital clock display that read 66:21. The maintenance panel was open. Inside, the core was empty.

“There’s your problem,” Leo announced.

Jason scratched his head. “Uh…what are we looking at?”

Leo thought it was pretty obvious, but Piper looked confused too.

“Okay,” Leo sighed, “you want the full explanation or the short explanation?”

“Short,” Piper and Jason said in unison.

Leo gestured to the empty core. “The syncopator goes here. It’s a multi-access gyro-valve to regulate flow. The dozen glass tubes on the outside? Those are filled with powerful, dangerous stuff. That glowing red one is Lemnos fire from my dad’s forges. This murky stuff here? That’s water from the River Styx. The stuff in the tubes is going to power the ship, right? Like radioactive rods in a nuclear reactor. But the mix ratio has to be controlled, and the timer is already operational.”

Leo tapped the digital clock, which now read 65:15. “That means without the syncopator, this stuff is all going to vent into the chamber at the same time, in sixty-five minutes. At that point, we’ll get a very nasty reaction.”

Jason and Piper stared at him. Leo wondered if he’d been speaking English. Sometimes when he was agitated he slipped into Spanish, like his mom used to do in her workshop. But he was pretty sure he’d used English.

“Um…” Piper cleared her throat. “Could you make the short explanation shorter?”

Leo palm-smacked his forehead. “Fine. One hour. Fluids mix. Bunker goes ka-boom. One square mile of forest turns into a smoking crater.”

“Oh,” Piper said in a small voice. “Can’t you just…turn it off?”

“Gee, I didn’t think of that!” Leo said. “Let me just hit this switch and—No, Piper. I can’t turn it off. This is a tricky piece of machinery. Everything has to be assembled in a certain order in a certain amount of time. Once the combustion chamber is rigged, like this, you can’t just leave all those tubes sitting there. The engine has to be put into motion. The countdown clock started automatically, and I’ve got to install the syncopator before the fuel goes critical. Which would be fine except…well, I lost the syncopator.”

Jason folded his arms. “You lost it. Don’t you have an extra? Can’t you pull one out of your tool belt?”

Leo shook his head. His magic tool belt could produce a lot of great stuff. Any kind of common tool—hammers, screwdrivers, bolt cutters, whatever—Leo could pull out of the pockets just by thinking about it. But the belt couldn’t fabricate complicated devices or magic items.