They moved on and it seemed to Yaz that some grey hint of light had insinuated itself about them. Even the malice of the ice felt blunted. Behind them, distant but not distant enough, a roar of primal rage echoed through the caverns. A moment later another howl rang out, louder and closer.

“We need light and speed,” Maya hissed.

Yaz tore her star from its pouch and woke its light, keeping it at a level that wouldn’t blind them after so long without sight. The ice had greyed to the point that it returned enough of a glimmer for them to avoid running into walls. They raced on with Maya in the lead, her sense of direction seemingly unerring even under the stress of pursuit.

Another hundred yards of panting and sprinting and they came blinking into the twilight of the ravine. The ice bridge stood only a short way off, the hidden river churning far below.

Maya led the way along the narrow rock ledge between the ice and the ravine. Yaz found herself wanting to shout at the girl to hurry while at the same time not wanting to move so swiftly across wet rock with the terrifying drop to one side and the dull malice of the grey ice wall to the other.

Maya reached the bridge and started to cross just as the Tainted began to boil out from tunnels and cavern mouths all along the dark side of the ravine.

“Run!” Maya shouted and followed her own advice, almost slipping from the bridge before she reached the relative safety of the far side.

Yaz released her fear in a wild scream and ran across the narrow span of wet ice. Quell pounded along after her.

“Yaz of the Ictha!” Theus’s voice boomed out, somehow louder than the roar of the hidden waters below them. “We have a deal!”

Yaz turned to see Theus standing at the place they had emerged from only a few moments earlier while the Tainted rushed past him. A couple of yards ahead of him a lean man in ragged skins paused to fling Quell’s iron spear, arching his whole body into the throw like an Ictha whaling on the Hot Sea. The length of iron arced over the heads of the Tainted in front of him, passing by the ear of a gerant closer to the bridge. Yaz saw the whole of the weapon’s trajectory in a frozen moment, lacking any time to move or even scream.

Petrick, at the start of the bridge and just yards ahead of those leading the chase, saw the spear, as did Quina ahead of him. Both of them, having hunska blood, rotated with inhuman speed, twisting their bodies since the ice wouldn’t give them the traction to turn.

The gleaming spearhead cut through the air toward Petrick’s chest. He found himself unable to move out of its way but somehow in a blur of motion he managed to deflect its flight so that it merely scored his ribs, passing beneath his armpit.

For a moment Yaz thought Petrick had won clear of the danger. His momentum carried him on toward the middle of the bridge but the shove he’d given the spear to turn its course had unbalanced him too. Again a heartbeat stretched into a paralysed age as Yaz watched the boy begin to fall with painful slowness, one foot slipping over the edge, arms pinwheeling.

Incredibly, Quina had turned and was running with fierce determination toward both Petrick and the Tainted. It seemed impossible that she would reach him though. The dark-haired girl ran faster than Yaz thought any human could, her feet sliding on the ice, lunging for Petrick’s outstretched hand.

Suddenly the moment released Yaz and ripped her scream from her.

Petrick fell, the horror on his face swallowed by the black mats of his hair rising around his face. The gap between his fingertips and Quina’s narrowed to inches, then suddenly yawned wide and he was gone.

Quina, unable to halt her advance on the ice bridge, leapt at the leading Tainted, a broad-shouldered woman, and kicked off from her chest. The action sent the woman back into her fellows, spilling one into the ravine, and sent Quina sliding back across the bridge onto the safety of Yaz’s side.

Yaz made her star a blaze of light and threw it into the cavern mouth behind her to block the way against the Tainted as Quina raced through. After that they ran, all of them flat out, Quina vanishing ahead, Maya falling behind, until at last, after many caverns and hundreds of yards, Yaz found her resolve and came to a halt. Quell pulled up alongside her, composed and ready where she was a breathless mess.

“We shouldn’t stop,” he said.

“But Maya!”

“She does things to the shadows. They won’t find her.”

The shouts of the Tainted were very distant now. Either the star had held them back until it burned itself into nothing or they had managed to bypass it but been delayed.

“We should go,” Quell said.

“Wait. She can’t be far behind.” Part of Yaz wanted to keep running, and not just to put distance between her and the Tainted, but to stop the truth of Petrick’s death catching up with her. Quina would feel it badly too; she had liked Petrick, sought time in his company. Perhaps she was still running from her grief somewhere far ahead of them.

“Let’s at least move to the wall then.” Quell stepped away from the centre of the chamber. “Can you dim the light in here?”

“Petrick fell!”

“I saw.” Quell nodded grimly, black against the bands of stardust running through the ice chamber.

“We should—”

“We need to get out of this place, back onto the ice where we belong.”

“I need to go back for Zeen. And the others. I need to save—”

“You can’t save everyone, Yaz. You just can’t. I don’t like that this place exists any more than you do. But it’s here for a reason. Nobody down here would survive on the ice. There’s nowhere for them to go. Even if the the ice does run out thousands of miles to the south . . . none of them could ever get there.” Quell raised his open hands, muscles straining against each other as if he were trying to claw the truth from the air itself and make her see it. “We can save ourselves. I thought we could save Zeen. We tried and we failed. The rest of them we were never going to be able to help.”

Yaz shook her head. “I don’t accept that. I can’t accept it.”

“We need to forget this hole. Everything will be alright again once we’re out. The regulator said—”

Yaz looked at him sharply. “The regulator said what?”

Quell frowned and rubbed his forehead as if it pained him. He shook the question away and beckoned her to join him by the ice. “Make it darker!”

Yaz stayed where she stood out in the open. “Quell—”

The sound of running feet interrupted her. One person with a light footfall. “Maya?”

As though summoned by her name Maya came hurrying out of the gloom, trailing shadows into the chamber, her knife in her fist, the blade bloody.

“We should go,” she said.