“We will come back shortly,” she heard Bayaz growling. “Leave the door ajar.”

“It’s always kept locked,” a voice answered. “That’s the rule. It’s been kept locked all my life, and I don’t plan to—”

“Then wait here until we come back! But go nowhere! I have many better things to do than sit waiting on the wrong side of your locked doors!” Keys turned. Old hinges squealed. Ferro’s fingers slid round a loose lump of stone and gripped it tightly.

The man in the dirty shirt was pulling the gates shut as she crept to the top of the steps. He muttered angrily as he fumbled with his keys, metal clinking. There was a dull thump as the stone clubbed him across his bald spot. He gasped, lurched forward, Ferro caught his limp body under the arms and lowered him carefully to the ground.

Then she set the rock down and relieved him of his keys with a hooked finger.

As Ferro lifted her hand to push the doors open, a strange sensation washed over her. Like a cool breeze on a hot day, surprising, at first, then delightful. A shiver, not at all unpleasant, worked its way up her spine and made her breath catch. She pressed her hand to the weathered wood, the grain brushing warm and welcoming against her palm. She eased the door open just wide enough to peer through.

A narrow bridge sprang out from the wall of the Agriont, no more than a stride across, without rail or parapet. At the far end it met the side of the Maker’s House—a soaring cliff of bare rock, shining black with the rain. Bayaz, Yulwei and Quai stood before a gate at the end of that strip of stone. A gate of dark metal, marked in the centre with bright circles. Rings of letters that Ferro did not understand. She watched Bayaz pull something out from the collar of his shirt. She watched the circles begin to move, to turn, to spin, her heart pounding in her ears. The doors moved silently apart. Slowly, reluctantly, almost, the three men passed into that square of blackness, and were gone.

The House of the Maker stood open.

Grey water slapped at hard stone below as Ferro followed them across the bridge. The rain kissed and the wind nipped at her skin. In the distance, smudges of smoke rose from the smouldering city and into the muddy sky, but her eyes were fixed on the yawning portal straight ahead. She loitered on the threshold for a moment, her hands clenched into fists.

Then she stepped into the darkness.

It was neither cold nor warm on the other side of the gate. The air was so still, and flat, and silent that it seemed to weigh heavily on Ferro’s shoulders, to press at her ears. A few muffled steps and the light had all faded. Wind, and rain, and the open sky were dimly remembered dreams. She felt she walked a hundred miles beneath the dead earth. Time itself seemed to have stopped. Ferro crept up to a wide archway and peered through.

The hall beyond was like a temple, but it would have swallowed whole even the great temple in Shaffa, where thousands called hourly out to God. It dwarfed the lofty dome where Jezal dan Luthar had been given a crown. It was an expanse that made even the vastness of ruined Aulcus seem petty. A place crowded with solemn shadows, peopled with sullen echoes, bounded by angry, unyielding stone. The tomb of long-dead giants.

The grave of forgotten gods.

Yulwei and Bayaz stood at its centre. Tiny, insect figures in an ocean of gleaming darkness. Ferro pressed herself to the cold rock, striving to pick their words out from the sea of echoes.

“Go to the armoury and find some of the Maker’s blades. I will go up, and bring… that other thing.”

Bayaz turned away, but Yulwei caught him by the arm. “First answer me one question, brother.”

“What question?”

“The same one I always ask.”

“Again? Even now? Very well, if you must. Ask.”

The two old men stood still for the longest time. Until the last echoes had faded and left only a silence as heavy as lead. Ferro held her breath.

“Did you kill Juvens?” Yulwei’s whisper hissed through the darkness. “Did you kill our master?”

Bayaz did not flinch. “I made mistakes, long ago. Many mistakes, I know. Some out in the ruined west. Some here, in this place. The day does not pass when I do not regret them. I fought with Khalul. I ignored my master’s wisdom. I trespassed in the House of the Maker. I fell in love with his daughter. I was proud, and vain, and rash, all this is true. But I did not kill Juvens.”

“What happened that day?”

The First of the Magi spoke the words as though they were lines long rehearsed. “Kanedias came to take me. For seducing his daughter. For stealing his secrets. Juvens would not give me up. They fought, I fled. The fury of their battle lit the skies. When I returned, the Maker was gone, and our master was dead. I did not kill Juvens.”

Again a long silence, and Ferro watched, frozen. “Very well.” Yulwei let fall his hand from Bayaz’ arm. “Mamun lied, then. Khalul lied. We will fight against them together.”

“Good, my old friend, good. I knew that I could trust you, as you can trust me.” Ferro curled her lip. Trust. It was a word that only liars used. A word the truthful had no need of. The First of the Magi’s footsteps rang out as he strode towards one of the many archways and vanished into the gloom.

Yulwei watched him go. Then he gave a sharp sigh, and padded off in the other direction, his bangles jingling on his thin arms. The echoes of his passing slowly faded, and Ferro was left alone with the shadows, wrapped in silence.

Slowly, carefully, she crept forwards into that immense emptiness. The floor glittered—snaking lines of bright metal, set into the black rock. The ceiling, if there was one, was shrouded in darkness. A high balcony ran around the walls a good twenty strides up, another far above that, then another, and another, vague in the half-light. Above all, a beautiful device hung. Rings of dark metal, great and small, gleaming discs and shining circles, marked with strange writings. All moving. All revolving, one ring about the other, and at their centre a black ball, the one point of perfect stillness.

She turned round, and round, or perhaps she stood still and the room turned about her. She felt dizzy, drunken, breathless. The bare rock soared away into the black, rough stones without mortar, no two alike. Ferro tried to imagine how many stones the tower was made of.

Thousands. Millions.

What had Bayaz said, on the island at the edge of the World? Where does the wise man hide a stone? Among a thousand. Among a million. The rings high above shifted gently. They pulled at her, and the black ball in the centre pulled at her most of all. Like a beckoning hand. Like a voice calling out her name.

She dug her fingers into the dry spaces between the stones and began to climb, hand over hand, up and up. It was easily done. As though the wall was meant to be climbed. Soon she swung her legs over the metal rail of the first balcony. On again, without pausing for breath, up and up. She reached the second balcony, sticky with sweat in the dead air. She reached the third, breath rasping. She gripped the rail of the fourth, and pulled herself over. She stood, staring down.

Far below, at the bottom of a black abyss, the whole Circle of the World lay on the round floor of the hall. A map, the coastlines picked out in shining metal. Level with Ferro, filling almost all the space within the gently curving gallery, suspended on wires no thicker than threads, the great mechanism slowly revolved.

She frowned at the black ball in its centre, her palms tingling. It seemed to hover there, without support. She should have wondered how that could be, but all she could think about was how much she wanted to touch it. Needed to. She had no choice. One of the metal circles drifted close to her, gleaming dully.

Sometimes it is best to seize the moment.