Like all the divinations Meg and I had retrieved during our adventures, the Dark Prophecy’s nightmarish prediction about Camp Jupiter remained burned into my mind:

The words that memory wrought are set to fire,

Ere new moon rises o’er the Devil’s Mount.

The changeling lord shall face a challenge dire,

Till bodies fill the Tiber beyond count.

After hearing that, Leo Valdez had raced across country on his bronze dragon, hoping to warn the camp. According to Leo, he had arrived just in time, but the toll had still been horrendous.

Frank must have read my pained expression.

“It would’ve been worse if it hadn’t been for you,” he said, which only made me feel guiltier. “If you hadn’t sent Leo here to warn us. One day, out of nowhere, he just flew right in.”

“That must have been quite a shock,” I said. “Since you thought Leo was dead.”

Frank’s dark eyes glittered like they still belonged to a raven. “Yeah. We were so mad at him for making us worry, we lined up and took turns hitting him.”

“We did that at Camp Half-Blood, too,” I said. “Greek minds think alike.”

“Mmm.” Frank’s gaze drifted toward the horizon. “We had about twenty-four hours to prepare. It helped. But it wasn’t enough. They came from over there.”

He pointed north to the Berkeley Hills. “They swarmed. Only way to describe it. I’d fought undead before, but this…” He shook his head. “Hazel called them zombies. My grandmother would have called them jiangshi. The Romans have a lot of words for them: immortuos, lamia, nuntius.”

“Messenger,” I said, translating the last word. It had always seemed an odd term to me. A messenger from whom? Not Hades. He hated it when corpses wandered around the mortal world. It made him look like a sloppy warden.

“The Greeks call them vrykolakai,” I said. “Usually, it’s rare to see even one.”

“There were hundreds,” Frank said. “Along with dozens of those other ghoul things, the eurynomoi, acting as herders. We cut them down. They just kept coming. You’d think having a fire-breathing dragon would’ve been a game-changer, but Festus could only do so much. The undead aren’t as flammable as you might think.”

Hades had explained that to me once, in one of his famously awkward “too much information” attempts at small talk. Flames didn’t deter the undead. They just wandered right through, no matter how extra crispy they became. That’s why he didn’t use the Phlegethon, the River of Fire, as the boundary of his kingdom. Running water, however, especially the dark magical waters of the River Styx, was a different story….

I studied the glittering current of the Little Tiber. Suddenly a line of the Dark Prophecy made sense to me. “Bodies fill the Tiber beyond count. You stopped them at the river.”

Frank nodded. “They don’t like freshwater. That’s where we turned the battle. But that line about ‘bodies beyond count’? It doesn’t mean what you think.”

“Then what—?”

“HALT!” yelled a voice right in front of me.

I’d been so lost in Frank’s story, I hadn’t realized how close we were getting to the city. I hadn’t even noticed the statue on the side of the road until it screamed at me.

Terminus, the god of boundaries, looked just as I remembered him. From the waist up, he was a finely sculpted man with a large nose, curly hair, and a disgruntled expression (which may have been because no one had ever carved him a pair of arms). From the waist down, he was a block of white marble. I used to tease him that he should try skinny jeans, as they’d be very slimming. From the way he glowered at me now, I guessed he remembered those insults.

“Well, well,” he said. “Who do we have here?”

I sighed. “Terminus, can we not?”

“No!” he barked. “No, we cannot not. I need to see identification.”

Frank cleared his throat. “Uh, Terminus…” He tapped the praetor’s laurels on his breastplate.

“Yes, Praetor Frank Zhang. You are good to go. But your friend here—”

“Terminus,” I protested, “you know very well who I am.”

“Identification!”

A cold slimy feeling spread outward from my Lemurian spice–bandaged gut. “Oh, you can’t mean—”

“ID.”

I wanted to protest this unnecessary cruelty. Alas, there is no arguing with bureaucrats, traffic cops, or boundary gods. Struggling would just make the pain last longer.

Slumped in defeat, I pulled out my wallet. I produced the junior driver’s license Zeus had provided me when I fell to earth. Name: Lester Papadopoulos. Age: Sixteen. State: New York. Photo: 100 percent eye acid.

“Hand it over,” Terminus demanded.

“You don’t—” I caught myself before I could say have hands. Terminus was stubbornly delusional about his phantom appendages. I held up the driver’s license for him to see. Frank leaned in, curious, then caught me glaring and backed away.

“Very well, Lester,” Terminus crowed. “It’s unusual to have a mortal visitor in our city—an extremely mortal visitor—but I suppose we can allow it. Here to shop for a new toga? Or perhaps some skinny jeans?”

I swallowed back my bitterness. Is there anyone more vindictive than a minor god who finally gets to lord it over a major god?

“May we pass?” I asked.

“Any weapons to declare?”

In better times, I would have answered, Only my killer personality. Alas, I was beyond even finding that ironic. The question did make me wonder what had happened to my ukulele, bow, and quiver, however. Perhaps they were tucked under my cot? If the Romans had somehow lost my quiver, along with the talking prophetic Arrow of Dodona, I would have to buy them a thank-you gift.

“No weapons,” I muttered.

“Very well,” Terminus decided. “You may pass. And happy impending birthday, Lester.”

“I…what?”

“Move along! Next!”

There was no one behind us, but Terminus shooed us into the city, yelling at the nonexistent crowd of visitors to stop pushing and form a single line.

“Is your birthday coming up?” Frank asked as we continued. “Congratulations!”

“It shouldn’t be.” I stared at my license. “April eighth, it says here. That can’t be right. I was born on the seventh day of the seventh month. Of course, the months were different back then. Let’s see, the month of Gamelion? But that was in the wintertime—”

“How do gods celebrate, anyway?” Frank mused. “Are you seventeen now? Or four thousand and seventeen? Do you eat cake?”

He sounded hopeful about that last part, as if imagining a monstrous gold-frosted confection with seventeen Roman candles on the top.

I tried to calculate my correct day of birth. The effort made my head pound. Even when I’d had a godly memory, I hated keeping track of dates: the old lunar calendar, the Julian calendar, the Gregorian calendar, leap year, daylight savings time. Ugh. Couldn’t we just call every day Apolloday and be done with it?

Yet Zeus had definitely assigned me a new birthdate: April 8. Why? Seven was my sacred number. The date 4/8 had no sevens. The sum wasn’t even divisible by seven. Why would Zeus mark my birthday as four days from now?