As I breathe in, I feel a tingle in my throat.

“I have given you agua respire,” she says. “You will be able to breathe water for one cycle of the sun.”

I nod, unable to form words.

The sea nymph turns back to Griffin. “I will lead her to the palace.”

He smiles. “Thank you.”

“This shall settle our score?” she asks. When he nods, she turns back to me and takes my hand. “Do not be frightened.”

I snort. As if I’m scared of anything.

But as she leads me past my friends, toward the water, a tiny taste of fear touches my tongue. I’m about to go deep into the Mediterranean, to breathe water as I seek a forbidden palace. Phoebe, Griffin, and Troy wave good-bye. I wave back, then follow the nymph into the sea.

I tell myself that panic is a normal reaction. It’s not every day a girl tries to breathe water. I’d be more concerned if I wasn’t scared. With the sea nymph at my side, I suck in my first lungful of water—bracing for the terror that will come. Water flows in and out of me like I was born to it. She smiles and—before I can adjust to the idea that I’m breathing water—takes off across the seafloor, pulling me with her. We speed over seaweed meadows, through dark, rocky outcroppings, and around fishing lines that reach down from the surface above. She swims faster than any fish I’ve ever seen.

I’m not sure if she’s in a hurry to get this over with or if she’s trying to keep me from being able to retrace our steps—or, more accurately, our kicks. Whatever the reason, it seems like only a few minutes have passed when she slows our pace over what looks like an underwater canyon.

“Hold tight,” she says. A heartbeat later we’re diving fast, deep into the canyon below.

We reach the canyon floor in about five seconds and then we’re swimming forward again, weaving through the rocky cliffs at hyperspeed. Suddenly, the canyon walls are gone and we emerge in a massive underwater chamber. A giant cave.

And right smack in the center of the giant cave is a giant castle.

“Poseidon’s palace,” I whisper.

“I can take you no farther,” she says. “You must find your own way inside.”

“Okay,” I say, nodding and trying to give myself courage for the task ahead. “I’ll be as fast as I—”

“To get home,” she interrupts, making it clear she won’t be waiting for me, “follow the canyon path until you can swim for the surface. From there, I believe you can get yourself home.”

Right. Once I’m out of Poseidon’s protection, beyond the range of the magic that defends his palace, I can autoport back to Serfopoula.

“Thank you,” I say. “This means a lot—”