“Come on.” Arden gestured for us to follow her with the hand that wasn’t full of firefly. She led us to a small door near the front of the shop and opened it, revealing a narrow flight of stairs descending beneath the building. She started down, leaving us no choice but to follow. Tybalt went last, and closed the door behind himself, cutting the light to almost nothing. Only almost: the firefly in Arden’s hand was glowing brighter than ever. The light seeped through her fingers, lessening the darkness just enough to make it navigable to fae eyes.

Arden didn’t speak as she walked down the stairs to the basement below. It was a large, cavernous room that appeared to exactly mirror the bookstore over our heads. Support pillars broke up the space, explaining why several hundred paperbacks weren’t crashing down on our heads. Everything smelled of fresh sawdust and old dampness, the clean kind that naturally built up underground. It spoke of growth and potential, not decay.

“Shield your eyes,” Arden said, and flicked a switch on the wall. Bulbs came on overhead, almost blinding after the darkness. She opened her hand, letting the firefly free, and released her human disguise in the same motion.

Her magic smelled like redwood bark and blackberry flowers. Her hair was the color of blackberries, so black it was virtually purple, with strange, glossy undertones. Her eyes stayed mismatched, but instead of brown and blue, they were polished pyrite and shifting mercury silver. No wonder a somewhat alien blue had been the best she could do. Those were eyes designed to resist concealment. Her ears were delicately pointed, and her bone structure had changed subtly, but those things were almost afterthoughts. Nothing human had those eyes.

She glared at us as the firefly circled her head and came to rest once more on her chest. “Who sent you?”

“The Luidaeg.” I pulled the flask of fireflies out of my jacket pocket, holding it up. Arden gasped. “She thought we might have trouble finding you, so she gave us these.”

Arden’s surprise quickly faded into wariness. “I don’t believe you.”

“Of course you don’t.” I tucked the flask away again as I released my human disguise. I smelled pennyroyal, and knew without looking that Tybalt was doing the same thing, both of us trying to convince our reluctant Princess that we meant her no harm. We didn’t look like the Queen’s guards. I was wearing an increasingly dingy ball gown, and Tybalt was the wrong species. “We haven’t been properly introduced. My name is Sir October Daye, Knight of Lost Words, in service to Duke Sylvester Torquill of Shadowed Hills.” I didn’t identify my race. The human in my background would be easy enough for her to see, and for the moment, it was better if I didn’t try to explain the situation with my mother.

For once, my name brought no flicker of recognition or reminder of things I hadn’t necessarily intended to do. Arden just frowned, and said, “I remember Duke Torquill. He was a nice man.”

“He still is.”

“I am Tybalt, King of the Court of Dreaming Cats,” said Tybalt. “I knew your father.”

“So you said, but what makes you sure he was my father?” Arden focused her frown on him. It was a bit of a relief to see her glaring at someone else. “I never said I was your girl. Maybe I just took you guys down here because I didn’t want you talking crazy in front of Jude. She doesn’t know.”

“That’s good; mortals shouldn’t,” I said. “You didn’t have to say it. The fireflies know.”

“You have your father’s eyes,” added Tybalt. “It’s no wonder you had to work so hard to hide yourself. Anyone who knew the King would have looked at you and known you for his child. I am so sorry for your loss.”

Those words seemed to seal any hope Arden had that we could be convinced she was really Ardith, bookstore clerk, and not Arden, Princess in the Mists. Her face crumpled, tears springing up in her mismatched eyes. “No one said that to us,” she said. “No one knew how much we’d lost. Father was gone, and Mother . . .”

Understanding hit me. There was an element we’d missed, someone who should have either whisked the children safely out of the Kingdom or backed their claim to their father’s throne. “What happened?”

“She was one of his servants at the Court,” said Arden. She sniffled. “It was how they made sure no one was suspicious about them spending time together. It was like a game they played. They made sure we knew the rules, so we wouldn’t get mad at Father for refusing to acknowledge her, or mad at Mother for letting him ignore her. It was even fun, sometimes, when she brought us to the Court and made us wear disguises and pretend we were changelings, or servant-children, or fosters. We learned about hiding.” She reached up, touching the corner of her silver-mercury eye, and added, “We had a nursemaid to spin our illusions for us, back then. We didn’t have to depend on our own.”

“That makes sense,” I said, not wanting to interrupt the flow of her story, but not wanting her to think I wasn’t listening.

“When the earthquake came . . . things were falling everywhere. Nolan’s leg was hit when some rocks came out of the wall. I went running, looking for Mother. We weren’t supposed to talk to her when we were at Court. I broke the rules.” For a moment, her expression was a child’s, filled with the quiet conviction that breaking the rules somehow caused everything that followed. “The earthquake was still happening. I found her in one of the bedchambers, where she’d been changing the sheets. She was already . . .” She closed her eyes. “She was gone.”

I blinked. “Wait. She was dead? Did something fall and hit her?” Some of the chandeliers I’d seen in noble knowes could crush an adult, if the chandelier was falling and the adult was unlucky.

“No.” Arden opened her eyes. “Her throat was slit. She was murdered. My father was, too. There’s no way he died in the quake. He was Tuatha de Dannan. He was a King. He would have died saving his people, if he died at all. Instead, they said he was crushed. Just crushed. That’s not possible. That’s not my father. Someone killed them, and they would have killed Nolan and me if Marianne—our nursemaid—hadn’t taken us away before anyone realized who we were. So, yes, you found the missing Princess in the Mists. Now please, save my life, and leave.”

“Oh, oak and ash,” I whispered. People had always suspected that King Gilad was assassinated: Oleander de Merelands was in the Kingdom at the time, and her presence combined with his death was too convenient to ignore. This was as close as we could get to proof without questioning the night-haunts. Arden had been orphaned, and her parents had been murdered. “I’m so sorry.”