“On the bright side,” Hedge told Mellie, “we got enchiladas and I scored some awesome nunchaku!”

Mellie gazed heavenward, perhaps wishing she could go back to her simple life as an unmarried cloud.

As for Meg McCaffrey, she had regained consciousness and looked as well as she ever looked—just slightly greasier thanks to the first-aid ministrations of Aloe Vera. Meg sat at the edge of the pool, trailing her bare feet in the water and stealing glances at Joshua Tree, who stood nearby, brooding handsomely in his khakis.

I asked Meg how she was feeling—because I am nothing if not thoughtful—but she waved me off, insisting she was fine. I think she was just embarrassed by my presence as she tried to discreetly ogle Joshua, which made me roll my eyes.

Girl, I see you, I felt like saying. You are not subtle, and we really need to have a talk about crushing on dryads.

I didn’t want her to order me to slap myself, however, so I kept my mouth shut.

Grover distributed enchilada plates to everyone. He ate nothing himself—a sure sign of how nervous he felt—but paced the circumference of the pool, tapping his fingers against his reed pipes.

“Guys,” he announced, “we’ve got problems.”

I would not have imagined Grover Underwood as a leader. Nevertheless, as he spoke, all the other nature spirits gave him their full attention. Even Baby Chuck quieted down, tilting his head toward Grover’s voice as if it was something interesting and possibly worth kicking.

Grover related everything that had happened to us since we’d met up in Indianapolis. He recounted our days in the Labyrinth—the pits and poison lakes, the sudden wave of fire, the flock of strixes, and the spiral ramp that had led us up to these ruins.

The dryads looked around nervously, as if imagining the Cistern filled with demonic owls.

“You sure we’re safe?” asked a short plump girl with a lilting accent and red flowers in her hair (or perhaps sprouting from her hair).

“I don’t know, Reba.” Grover glanced at Meg and me. “This is Rebutia, guys. Reba, for short. She’s a transplant from Argentina.”

I waved politely. I’d never met an Argentinian cactus before, but I had a soft spot for Buenos Aires. You haven’t really tangoed until you’ve tangoed with a Greek god at La Ventana.

Grover continued, “I don’t think that exit from the maze has ever been there before. It’s sealed now. I think the Labyrinth was helping us, bringing us home.”

“Helping us?” Prickly Pear looked up from her cheese enchiladas. “The same Labyrinth harboring fires that are destroying the whole state? The same Labyrinth we’ve been exploring for months, trying to find the source of those fires, with no luck? The same Labyrinth that’s swallowed a dozen of our search parties? What does it look like when the Labyrinth isn’t helping us?”

The other dryads grumbled in agreement. Some bristled, literally.

Grover raised his hands for calm. “I know we’re all worried and frustrated. But the Burning Maze isn’t the entire Labyrinth. And at least now we have some idea why the emperor set it up the way he did. It’s because of Apollo.”

Dozens of cactus spirits turned to stare at me.

“Just to clarify,” I said in a small voice, “it’s not my fault. Tell them, Grover. Tell your very nice…very spiny friends it isn’t my fault.”

Coach Hedge grunted. “Well, it kind of is. Macro said the maze was a trap for you. Probably because of the Oracle thingie you’re looking for.”

Mellie’s gaze ping-ponged between her husband and me. “Macro? Oracle thingie?”

I explained how Zeus had me traveling around the country, freeing ancient Oracles as part of my penance, because that’s just the sort of horrible father he was.

Hedge then recounted our fun shopping expedition to Macro’s Military Madness. When he got sidetracked talking about the various types of land mines he’d found, Grover intervened.

“So we exploded Macro,” Grover summed up, “who was a Roman follower of this emperor. And he mentioned some kind of a sorceress who wants to…I dunno, do some evil magic on Apollo, I guess. And she’s helping the emperor. And we think they put the next Oracle—”

“The Sibyl of Erythraea,” I said.

“Right,” Grover agreed. “We think they put her at the center of the maze as some sort of bait for Apollo. Also, there’s a talking horse.”

Mellie’s face clouded over, which was unsurprising since she was a cloud. “All horses talk.”

Grover explained what we’d heard in the dumpster. Then he backed up and explained why we’d been in a dumpster. Then he explained how I’d wet my pants and that was why I was wearing hot-pink camo.

“Ohhh.” All the dryads nodded, as if this was the real question that had been bothering them.

“Can we get back to the problem at hand?” I pleaded. “We have a common cause! You want the fires stopped. I have a quest to free the Erythraean Sibyl. Both those things require us to find the heart of the maze. That’s where we’ll find the source of the flames and the Sibyl. I just—I know it.”

Meg studied me intently, as if trying to decide what embarrassing order she should give me: Jump in the pool? Hug Prickly Pear? Find a shirt that matches your pants?

“Tell me about the horse,” she said.

Order received. I had no choice. “His name is Incitatus.”

“And he talks,” Meg said. “Like, in a way humans can understand.”

“Yes, though normally he only speaks to the emperor. Don’t ask me how he talks. Or where he came from. I don’t know. He’s a magical horse. The emperor trusts him, probably more than he trusts anyone. Back when the emperor ruled ancient Rome, he dressed Incitatus in senatorial purple, even tried to make him a consul. People thought the emperor was crazy, but he was never crazy.”

Meg leaned over the pool, hunching her shoulders as if withdrawing into her mental shell. With Meg, emperors were always a touchy subject. Raised in Nero’s household (though the terms abused and gaslighted were more accurate), she’d betrayed me to Nero at Camp Half-Blood before returning to me in Indianapolis—a subject we’d skirted without really addressing for a while. I did not blame the poor girl. Truly. But getting her to trust my friendship, to trust anyone after her stepfather, Nero, was like training a wild squirrel to eat out of one’s hand. Any loud noise was liable to cause her to flee, or bite, or both.

(I realize that’s not a fair comparison. Meg bites much harder than a wild squirrel.)

Finally she said, “That line from the prophecy: The master of the swift white horse.”

I nodded. “Incitatus belongs to the emperor. Or perhaps belong isn’t the right word. Incitatus is the right-hand horse to the man who now claims the western United States—Gaius Julius Caesar Germanicus.”

This was the dryads’ cue for a collective gasp of horror, and perhaps some ominous background music. Instead, blank faces greeted me. The only ominous background sound was Baby Chuck chewing the Styrofoam lid of his father’s #3 dinner especial.

“This Gaius person,” said Meg. “Is he famous?”

I stared at the dark waters of the pool. I almost wished Meg would order me to jump in and drown. Or force me to wear a shirt that matched my hot-pink pants. Either punishment would have been easier than answering her question.