But I didn’t. I stared at my dead sister until I began to sob, and then I cried for what seemed like an eternity, until at last my tears ran dry. Still I did not wake, and by that time I had forgotten I was dreaming. I only knew that I had failed my sister, and that for my punishment I must live with that sin forever. I lay down beside her—the cold, clammy skin was horrible to touch, but I curled closer—and I stared into the darkness and waited.

And waited.

I cried again, and stopped. The tears itched and dried on my face. And I waited, until my vision had faded away, leaving me in total darkness, and I could not feel my sister or the stone slab, only cold all around me.

Finally Ignifex shook me awake. I huddled shaking in his arms, and would not tell him what I had dreamt. All my life had been veined with hatred; I didn’t want to remind us both of the feud between us and maybe awake it again.

But after that night, I couldn’t entirely ignore the knowledge that it was still there.

“Our sky is the dome of that room, right?” I said one evening.

“More or less,” said Ignifex without looking up.

We were in a room with wood-paneled walls and a great fireplace; the entire floor was covered with puzzle pieces that drifted as if moved by invisible currents. The only piece of furniture was a plump maroon couch with gold tassels; I lay draped across the couch while Ignifex sat cross-legged on the floor and tried to assemble the puzzle.

I was trying to read a book about astronomy, but half the words were burnt out. I wanted to know why the Kindly Ones had censored thoughts of the sky and the ancients’ theory of celestial spheres.

“But no one’s ever seen you looming over the horizon,” I said thoughtfully, watching his shoulders move. For once he was not wearing his coat, and the firelight glowed through the white fabric of his shirt.

Ignifex lunged forward, hair swinging, to catch a drifting piece with one finger. He drew it back and fitted it into a corner between two other pieces; it trembled a moment and then was still.

“You would know better than I,” he said, tapping a finger thoughtfully against what he’d assembled. So far it showed part of a castle.

“And when you’re in that room, it looks like a model instead of the whole world. What would happen if you dropped a rock on it?”

He finally looked up, the firelight flickering in his eyes. “And they call me cold-blooded.”

“I wouldn’t do it, I just want to know how this house works.”

“I’m not sure even the Kindly Ones know that.”

“Most of the other rooms have windows,” I said, as much to myself as him. “And I can always see the sky through them. They’re inside Arcadia and Arcadia is inside that room, so . . . that’s the only real place, isn’t it?”

“Or that room is the only place that isn’t real. Does it matter?” He caught a piece that had drifted up from the floor and twisted it between his fingers.

I leaned forward. “What was that box?”

“What box?”

I poked his head. “You know, the one I picked up and then you bore down on me like all the Furies rolled into one.”

“Oh, that box.” He stared at the fire, still twirling the puzzle piece in one hand. “I don’t know.”

“More of your philosophy?”

“No, when I . . . first was, they told me that if I opened the box, it would be the end.”

Upon the box were written the words “AS WITHIN, SO WITHOUT.” That was a Hermetic saying: was the box too, like the house, a Hermetic working?

“The end of you?” I asked slowly. “Or Arcadia?”

“They did not specify, and shockingly, I did not put their warning to the test.” He smiled up at me and slipped the puzzle piece into my hand. “This world’s already seen enough Pandoras, don’t you think?”

I looked at the puzzle piece. It showed stones, and lying against them either a rose petal or a drop of blood. Or perhaps a flame.

“What’s this?” I asked curiously.

“It’s part of this house, so who knows?” The firelight glinted in his eyes as he looked up at me.

I rolled my eyes. “You are entirely too pleased with your own sayings sometimes. I suppose you even have a quip prepared for your death?”

“Are you planning to find out?”

I trailed my fingers through his hair. His scalp was warm and dry beneath my fingertips. It startled me, as it still did sometimes, that he was solid and alive; that this wild, unnamable creature was not a phantom but sat still beneath my hand. That the demon who ruled all our world was mine.

“I don’t know,” I said. “Have you come up with any reasons why I shouldn’t?”

He sat up straighter and kissed me. I leaned forward, kissing him back, until I lost my balance and we both tumbled to the ground, with me landing on top of him.

All around us, loose puzzle pieces flew into the air as lightly as feathers. Once airborne, they did not fall but began a slow, stately swirl about the room, like a formal dance. From the corner of my eye, I saw the ragged portion that Ignifex had assembled was dissolving too, little castle bits lifting up into the air, their collective meaning forgotten. Something—half memory, half guess—niggled at my mind.

Then Ignifex reached up to touch my face. I leaned down to kiss my husband, and thought no more of puzzles.

I wanted to forget. I wanted so much to think only of Ignifex, to make his house into my home. Most of all, I did not want to remember I was on a mission to avenge my mother and save my world.

But more and more, I thought of Astraia. And Mother, and Father, and Aunt Telomache. I thought of Elspeth’s wormwood smile and the one time I had spied her weeping. I thought of all the other people in the village, who must always be afraid that this year the tithe wouldn’t work; of the Resurgandi, who had labored for two hundred years and put their trust in me; of Damocles and Philippa and the people screaming in my father’s study.

Who was I, to consider my happiness more important?

“You’re solemn today,” said Ignifex one morning. We were in a large room with white marble floors and walls covered in ivy. The ceiling was all tree branches, with one window at the center. Under the diffuse circle of sunlight pooled a thick red rug; we had brought books and a pot of tea, but instead of doing research, I ended up resting my chin on a pile of books and staring at the ivy, while Ignifex sipped tea and stroked my hair.

“It’s autumn,” I said. “I can see the trees turning through the windows.”

He tucked a strand of hair behind my ear.

“It’s going to be the Day of the Dead soon,” I said.

“Sounds gruesome.”

“It’s a festival.” I looked at him over my shoulder. “The only one that gentry and peasants share. We celebrate Persephone going down to Hades for the winter, they remember Tom-a-Lone getting his head cut off by Nanny-Anna. Everybody makes grave offerings, then there’s a great sacrifice to Hades and Persephone, and that night there’s a bonfire and they burn a straw Tom-a-Lone dressed up in ribbons.”

I had always loathed the trip to the graveyard. Astraia and I were bundled into our best black outfits, stiff with ribbons and lace, and we would kneel for an hour as Father and Aunt Telomache burned incense and recited endless prayers together, their faces nauseatingly pious. Astraia would sniffle through the whole affair, while I would stare at the carved words “THISBE TRISKELION” and carefully not ask Father why he didn’t just make love to Aunt Telomache atop the grave and have done with it.

“Charming way to honor a god,” said Ignifex.

“Well, he’s already dead. He needs a pyre.”

Ignifex raised his eyebrows questioningly.

I sighed. “I suppose a demon wouldn’t pay attention to the hedge-gods. The story goes, Tom was the son of Brigit, who’s a bit like Demeter and Persephone combined. She rules everything underground, seeds and the dead alike. Anyway, Tom fell in love with Nanny-Anna, the hedge-goddess who dances with the birds. But Brigit was jealous; she didn’t want to share her son with a lover. So she told Nanny-Anna that Tom was mortal like his father—true—but that if his lover cut his head off, he’d turn into a god. Which was also true, but what she didn’t tell her was that he would turn into a dead god, trapped in the darkness beneath the earth. So that’s why he’s called Tom-a-Lone: because he’s sundered from his love, Nanny-Anna, except for the Day of the Dead, when he can meet her from sunset to sunrise. Though really the name doesn’t make sense, since he still has Brigit and all the dead to keep him company.” I shrugged. “The scholars say it’s a corruption of the story about Adonis and Aphrodite, but the peasants swear up and down he’s real as Zeus. Anyway, that’s why the day is for mourning the dead but the night is for drinking and lovers.”