“What the—” I opened my eyes, and my mouth fell open. We weren’t in the Underworld anymore. Instead we stood in a lush garden with trees as tall as the bright blue sky, and exotic flowers surrounded us, turning toward us as we appeared.

“Welcome to the Underworld,” said James. “Or at least the part of it where the souls stay. Come on.”

He led me down a dirt path with Ava trailing behind us, strangely quiet for all of the wonder that surrounded us. I stared at the giant flora as we walked by, unable to hide my awe. It was as if I’d stepped into a fairy tale. Or fell down the rabbit hole.

“What is this place?” I said. “Is the entire Underworld like this?”

“No,” said James. “Look.”

He pointed through the trees at a girl swinging back and forth on a rope made of vines, her long hair swaying with her movements and her skin darkened from the sun. The same sun that had been replaced by crystal in the cavern before.

“Who’s that?” I whispered. “Is that Persephone?”

Ava snorted softly, and I gave her a dirty look.

“If only it were that easy,” said James with a hint of amusement in his voice. “Only the six siblings and Henry’s queen can travel like that down here, and since you haven’t learned how yet, we’ve got a hike ahead of us. That girl’s the reason we see all of this. Henry took you down into the Underworld once, right?”

I nodded. He’d done it to comfort me, to show me that my mother would be all right after the cancer won and she died. I hadn’t known at the time that my mother was actually immortal. That would’ve helped a little more.

“Central Park,” I said. “That was what it looked like to me. It’s where my mother and I used to go on summer afternoons.”

“That’s so sweet,” said Ava, looping her arm in mine. “Mine would be Paris, I bet. I could spend a millennium there and never get bored.”

We both waited for James’s answer, but instead he looked back at the girl in the distance. “This is her Eden. Because we’re immortal, the Underworld adapts to the closest mortal soul—her. Anywhere she goes, this is what she’ll see, and as soon as we get close enough to someone else, it’ll change.”

I watched her swing back and forth, her face tilted toward the sun and a smile dancing on her lips. She looked happy. The kind of happy I wished I could be. “She’s alone? Are they all alone?”

James gestured for us to follow. “Didn’t Henry—” He stopped and grimaced, and I bit back a retort. No, Henry hadn’t filled me in. “It depends. It’s part of what you’re going to be doing. Some people are reunited with loved ones, others aren’t. Sometimes people spend half their time alone and half of it with loved ones. There’s no hard and fast set of rules. The person has the kind of afterlife they expect, or at least the one they think they deserve.”

Oh. That. And if there were any questions or discrepancies, that was where Henry and I came in. “He explained that part,” I said. “Some people really spend the rest of forever alone?”

Ava’s grip on my arm tightened, and I squeezed back. That didn’t sound like heaven to me.

“You need to forget your expectations,” said James as we picked our way around an enormous weeping willow the color of cotton candy. “Everyone’s different. Sometimes religion plays a part, sometimes it doesn’t. Henry will explain all of this to you.”

Only if we all returned in one piece.

I knew what happened to mortals after they died, but if it came to it—if killing me was enough to convince Calliope to help subdue Cronus before he escaped—what would happen to me now that I was immortal? I would fade, I knew that much, but what did that mean? I’d always believed in some sort of afterlife even before I’d met Henry and discovered the truth. That belief had kept me sane during the years I’d spent watching my mother die, knowing I would see her again when it was over for me, too. I had no such certainty now.

I was so lost in my thoughts that I didn’t notice when the sky grew dark again. The sun was gone, replaced with the cavern walls from before, but this time the light didn’t come from crystal.

We stood on the banks of a lake of fire. Flames flickered toward my feet, and as I took a startled step back on the black sand, James and Ava began to walk around it as if it were nothing more than an annoyance.

And then I heard the screams.

They echoed through the cavern, filled with so much agony that I could feel it in my bones. A man cried out in a language I didn’t understand, and horrified, I squinted into the fire.

He hung from chains that faded into nothingness before they reached the ceiling. The lower half of his body was immersed in the lake, and his expression was twisted with pain I couldn’t imagine. His skin melted from the bone, dripping down into the fire, but as soon as it disappeared, new flesh replaced it.

He was being burned alive again and again without relief. His screams reverberated through the cavern and imbedded themselves in my memory, too tormented for me to ever forget them. I couldn’t look away, and the urge to do something—anything—rose within me, too strong to be ignored.

“We have to help him,” I said, but Ava held me back. I struggled against her, and James hurried toward us, taking my other arm.

“And how do you intend to do that?” he said. “By walking in there and burning up, as well?”

“I can’t die,” I said through gritted teeth as I tugged against them. “Remember?”

“That’s no reason to put yourself through that kind of pain,” said James. “You might not feel it on the first step, but you were mortal six months ago, and your body hasn’t forgotten that. You wouldn’t make it five feet, let alone there and back. Whatever he did, he believes he deserves it.”

I gaped at him, horror-struck. “He thinks he deserves being burned alive for eternity? What could possibly be that bad?”

“I don’t know,” he said. “When you’re queen, you can find out for yourself. Now let’s go. We don’t have time to waste.”

I couldn’t tear my eyes away from the man as James and Ava forced me to walk around the lake. Even after the Underworld turned into a rolling field with a yellow cottage nestled in the middle, I heard his screams echoing in my mind.

At least James had confirmed what I’d suspected. My body was adjusting, but it still remembered what it was like to be mortal. Glass bounced off my skin, I could fall from the top of the Empire State Building and walk away without a scratch, but I could feel the burn of fire.

“How long before I don’t feel pain anymore?” I said, my voice trembling.

“It’s different for everyone,” said James. “Maybe a few months, maybe a few years. It’s your mind that’s doing it, not your body.”

“But it will go away?” I said.

“Eventually.”

“What about pleasure?”

Ava slipped her hand into mine. “Kate, if none of us could feel pleasure, do you really think we’d do half the things we do?”

I managed a faint smile. “Good point.”

We walked in silence, passing through place after place after place. Some of them were as wonderful and lush as the garden; others were full of pain and torture. I all but ran through those, my head down as I tried to ignore the screams. Eventually they all blended together, forming a chorus of pain, and the more I heard, the more certain I became that Henry and the council had been wrong. I could never do this. I could never sentence people to that kind of eternity, no matter what their crimes had been.

Time lost all meaning as we wandered. James seemed to know where he was going, leading the way once he was sure I wasn’t going to try to run and help the people we passed, and Ava hung on to me. I lost count of the number of places we walked through—dozens? A hundred? I couldn’t remember them all. My feet ached and my leg felt as if the bone was breaking with every step I took, but finally in the middle of a forest, James stopped and set his bag down. “I think it’s a good time to rest.”