“They’re not my people. And there are no quantals among the Broken.” Yaz frowned.

“But they hunt the stars for quantals to use. They trade them, do they not?”

“That’s why they throw children down here,” Yaz breathed. “The priests of the Black Rock. They might want the stars even more than they want the iron.”

Erris shrugged, an odd thing to see. Metal grated on metal. “There may be other reasons. It doesn’t seem an . . . efficient . . . solution. But yes, those are reasons too. Any star should be worth a billion times its weight in metal, but I concede that the realities of life in a frozen wasteland might change that balance, especially if the ability to exploit them is rare.”

Yaz looked around. Her stomach growled, she licked dry lips with a dry tongue, her head ached, and her body felt sore. “How does this help me leave?”

“You should be dead, Yaz. Being this close to the void star would drive almost anyone else mad, their brain would bleed, they would die. Even most full-blood quantals couldn’t get within a hundred yards without their personality being torn apart. The human mind wasn’t built to withstand this power. It’s like fire. From a distance it lights the way. Closer up it warms us. Too close and we burn. With the stars it’s similar. At a distance there is light. Closer to us they open the Path to those who can find its power. Too close and they split our minds apart. The piece of you that longs to murder becomes its own creature. The part that is jealous, the part that lusts, your anger . . . all of them break away and find their own voice.”

Yaz nodded. “I can feel that. Voices in my head. A splitting pain.”

“It’s good you can feel something! I was starting to think you weren’t human at all.” Erris raised a metal hand. “Don’t be offended. It’s just that the city brought you here to die. It’s as if you had been thrown into a furnace and were standing there in the white heat and only now just beginning to sweat. It shouldn’t be. And yet it is.” He set his steel fingers to her shoulder and Yaz kept herself from flinching. “And I am glad of it. Truly.” He looked around and pointed at a section of the wall no different from any other. “That’s where we need to go. Look for the Path. This river of yours.”

Rather than argue that it was too soon Yaz let her eyes defocus, ignored the pain lancing through her skull, and looked beyond the world.

If the river were visible at all so close to her last touch then it should have been a gossamer thread far beyond reach. Instead the river roared all around her, a torrent rushing through the world’s impossible angles with a speed that might strip flesh from bone. The shock of it threw Yaz back against the wall and left her trembling.

“I saw it!”

“I noticed.” Erris bent his dark head.

“What do I do?”

Erris turned away and began clearing a path to the opposite wall, pushing aside heavy blocks from which black ropes emerged, metal casings, parts of . . . things. “You’re the expert, not me. But it shouldn’t be hard. Remember that the Missing have made this route for you. All you need to do is follow it. And take me with you.”

Yaz advanced along the cleared path toward the wall, kicking away small objects Erris had missed. One whirred alarmingly and scuttled away on pin-like legs to hide among the heaped debris to one side. She came to the wall as Erris hauled aside the last obstacle, metal squealing on stone.

“So, I just . . .” Yaz set her palms to the stone, finding it warm to the touch, warmer than ice anyhow. She gathered herself for the effort.

“You don’t need to pound your way through—use the Path to take us, let it show you the way.” He reached out to tap the stone with a steel finger. “We should probably hurry.” Another tap.

“Hurry?” Yaz looked back over her shoulder and favoured the impenetrable darkness where Erris’s face should be with her hardest stare. “Through a wall?”

“Yes.”

“Yesterday I was on the ice, where I had always lived. And now I’m miles below the rocks that are miles below the ice in a city built by the Missing, and I am being instructed on walking through walls by a man who might have died thousands of years ago and is talking to me from inside a body made of metal and . . . and I don’t know what else. All of which is to say: give me a gods-damned moment here.”

Erris had the wisdom to say nothing.

Yaz returned her attention to the wall. She could feel the pressure of the void star, feel it eroding who she was, prying apart the constituents of her mind. She leaned in and set her forehead to the stone. “How dangerous is this?”

“Less dangerous than staying here.”

“Will I get stuck? Lost in the rock?” When someone became separated from their clan the wind would lay them down in time. The snow would cover them. The ice would take them into itself, locked forever in its depth. “Will I die?”

Erris’s voice came soft now, almost free of distortion, almost how he had sounded under the warmth of the sun, standing with the grass waving around his feet. “I don’t know.”

“Thank you for showing me the trees,” Yaz said, a bittersweet pain around her heart as she remembered how they had looked. “At the end of the long night the Ictha take any oil that remains and melt ice. We build a windbreak and our elders dribble the water out . . . It freezes at once, but the skill is to build sculptures as it flows and freezes. They call it the garden.” The shapes had always reminded Yaz of veins, spreading and branching. They were tall and fragile and beautiful, built only for the wind to tear down. A rare Icthan extravagance. But for a while they lasted, and overhead the dragons’ tails lashed in the last of the night sky, the aurora, shifting, ghostly veils of colour. And when the light grew green and echoed within the branches of the ice garden the elders would sing a song without words, holding only loss. The burning of the oil was the only time, save for leaving the dead to the wind, that any Ictha ever wasted anything. Yaz had never understood it, nor known what lay behind the sorrow in the garden-song. “If I die here . . . well . . . I still will have seen trees. You taught me something. And for that I am grateful.” Perhaps it was the void star’s song eroding her barriers, or the accumulation of two long days since dropping into the pit, or just the fear that she would die, but Yaz found herself trembling, her eyes prickling, the breath threatening to catch in her throat. “Thank you for the flutterby too. And the grass.”

“Butterfly.” Erris bowed his head. “I’m sorry this has happened to you. You were thrown from the only life you knew. Maybe the only life you could imagine.” His metal hand rested beside hers against the wall. “I fell and lost my future too. The things I had wanted and hoped for. Small things maybe, foolish things, but they were mine and it still burns me even though all those times are gone and forgotten. It still hurts. Both of us . . . we’ve fallen into lives we don’t understand and didn’t ask for.”