Maya nodded. “And so every Axit child is told that if they are ever thrown into the pit it is their duty to discover the secrets of the iron and escape with that knowledge.”

“And what then?” Yaz asked. “They say thank you very much and throw you back in?”

Maya scowled but Yaz could tell that her question had hit the mark.

“Do you know how they get the iron out?” Yaz asked.

Maya nodded. “They put stars in two sigil pots and lower them on wires to rapidly melt two narrow holes all the way through the ice. The water pours out through the roof of the city cavern. They pour coal down one of the holes and clog it up. Then they call a coal-worm somehow and it follows the line of coal, melting a big wide hole, with all the water draining through the other narrow hole they made.

“The worm veers off before it falls through the ceiling but they can melt through the last bit themselves. And then they lower a cage for the iron loads and haul them up. When it’s all finished ice-workers at this end seal the hole so a new pit doesn’t start, and the flow of the ice squeezes the rest shut after a while. When the Pit of the Missing moves too far away from the city they start a new one here. They do that about every thirty years or so.”

Yaz and Quell looked at Maya in astonishment.

“You did not hear all that just eavesdropping for a few days!” Yaz said.

“And no elder would have laid all their secrets bare to someone so new, surely?” Quell frowned.

“I asked Petrick,” Maya said. “Made him feel awkward for not knowing. Then I spied on him during the sleep periods until he went and demanded that Arka give him the answers.” She shrugged. “You just have to know how people work. Petrick didn’t care about not knowing until it put him in the same basket as a girl still wet from her drop. Then he had to know. The next collection is in twenty-three days.”

Yaz’s mind plagued her with images of Petrick’s slow, inevitable fall from the bridge. He’d been the one to save her from Hetta when she was still dripping from the pools. She shook the thoughts away. “You’re thinking we should ride up in the cage?”

“I am.” Maya nodded.

“In twenty-three days? Theus will have taken all the caverns by then, unless Pome regains control of his hunter. And if that happens Pome will have all of the caverns and we won’t be much better off than we would with Theus. That new star of Pome’s has tainted him . . . as if he weren’t bad enough before.”

“We could hide in the city.” Even Maya sounded doubtful, and she could hide herself in shadow.

“There are things down there that would kill us quicker than Pome or Theus would,” Quell said.

“You have a better idea?” Maya asked, her expression growing fierce again.

Quell turned away, his hands in fists at his sides. He started to walk down the long slope toward the city cavern, kicking at the ground as he went. Yaz had never seen him like this, angry, unsure of himself.

She was on the point of starting to follow when he spun round and marched back, his face dark. “Yaz . . .” He faltered before her stare.

“What is it?”

He reached into his furs and brought out a small yellow star, no bigger than the nail on his little finger. Holding it seemed to pain him and he held it out to her, gesturing for her to take it.

Yaz lifted it from between Quell’s finger and thumb without touching it and let it hang in the air between them alongside the as yet unasked questions about its existence. The star shone a sour yellow light and its song seemed out of key. Something about it made her think of black strips of skin fluttering in a breeze.

“He said I could save you,” Quell said helplessly. “But I had to lie to you. If you knew he was behind it then—”

“But you were behind it . . . you came to save me.” Yaz had never understood when the stories spoke of heartbreak but something was breaking in her chest now. “Quell?” She drew in a shuddering breath to steady her voice. “You stole the harness ropes to—”

“They gave the ropes to me because the regulator told them to.” Quell hung his head. “I didn’t even need the ropes. The priest told me I would be safe if I leapt in. But I was too scared to jump . . .”

Yaz snatched the yellow star from the air. Instantly she had flashes of scars seared across face and scalp, the sigil shapes familiar from the walls of the Missing’s city. The gaunt and sour lines of the priest’s face. The Icthan whiteness of his irises. She released it as if bitten. “You used this to schedule an early collection of iron?”

Quell nodded. “I can’t talk to him but he said if I held it and thought hard about you he would know I was ready and would arrange the collection.”

“So he knows we’re coming. They’ll all be waiting for us out on the ice when they haul us up? Ready to capture us.” Yaz shook her head. “Quell, how could you?”

“How could I what?” He sounded angry now. “How could I want to bring you home? You just threw yourself into the hole. You didn’t have to. You left us. You left me! And now you’re cross with me because I needed help to save you?”

“You should have told me you were working with the regulator.”

“I was scared you wouldn’t come back with me. I didn’t understand what had happened to you. To your mind.” He took a breath and spread his hands in incomprehension. “You threw yourself down the pit, Yaz!”

“Zeen—”

“Yes, Zeen! I know. It was bad. But a score of children go down the pit every gathering. Nobody throws themselves after them. Nobody. Not even the mothers. Certainly not a sister!”

“Well, maybe they should!” Yaz practically screamed the words and the sound echoed back from the roof above the long slope, fading into silence as the two of them stood facing each other, fists balled, breathing hard as if they’d been wrestling.

That she had jumped. That was what stood at the heart of it. What had pushed her and what had pulled her. Theus had said that everyone was searching for themselves, and evil as he was Yaz saw a certain truth in his words. She had always been a mystery to herself, a battle between the pieces that Theus said the Missing cut away and discarded. Had she been escaping her life? Saving Zeen? Railing against the injustice that she had been saved from only by a hair’s breadth? Quell stared at her, his eyes demanding an answer. Yaz could only shake her head.

Maya was the first to speak again. “Then we wait here a day or two and ride the collection cage up.” She began to walk down the long slope, and after a short pause, Quell turned to follow her.

Yaz watched them go, past the warding pillars and into the glow of the city cavern. She held the regulator’s star between finger and thumb, willing its light down to a whisper and then down again until she held nothing but a translucent yellow globe. She found a pocket for it and released a long, slow sigh. Then, still deep in her thoughts, she followed the other two into the ruined city.