The pyramids were larger up close, which is the habit of pyramids. Three of them stood in a row, their sides scored with marks that might have been wind or might have been writing. Mihao walked around the tallest twice before he found the door, and only found it then because his beard tugged him towards it like a dog on a lead.

There was no handle and no keyhole. In the centre of the stone, carved deep, was an eye. It blinked.

“Name,” said the door, in a voice like a coffin lid sliding. Mihao gave it. The eye considered him. “That is what you are called,” it said. “I asked what you are.”

He did not know. He stood in the hot dark for a long time, feeling foolish, while the runes around the eye flickered through every name the door had ever been given. At last he pulled a single hair from his beard and held it up. It shone, and curled, and wrote itself on the air: a book with a cat curled around it. The door looked at the shape for a long moment. Then, slowly, as though recognising an old friend, it opened.

Below lay a city: streets of pale stone, dry canals, lamps that lit themselves as he passed and went out again behind him. Everywhere there were cats. Carved, gilded, and, Mihao realised with a start, real. They sat on thrones and benches and doorsteps with their eyes closed, breathing so slowly it could hardly be called breathing.

These were the cat-kings of Ankhara and all their people. When the Hollow first came to the desert, they made a terrible bargain with time. A thing that sleeps is not quite forgotten, they reasoned. So they slept, and their names stayed carved and sharp above their heads, and the city waited for someone to come down and remember them.

The queen woke for one hour in every hundred years, and Mihao had the luck, or the misfortune, to arrive in it. She was a long, lean cat the colour of evening sand, with a collar of lapis and eyes like two lit lamps. She did not get up. Queens of Ankhara do not get up for anyone.

“The Library sent us a leaf when it broke,” she said. “We keep it behind the Lion. You may try for it, Keeper. Everyone else who tried is now part of the floor.” She yawned enormously. “Mind the Lion’s question. He only ever asks one, and he never asks it fairly.”

Akhet was a lion of black stone as tall as a house, lying across the last doorway with his paws crossed. He was the first of the old guardians Mihao would meet, though not the last, and he smelled faintly of incense and of rain that had fallen ten thousand years ago.

“Keeper,” said Akhet, which was interesting, because nobody had told him. “One question. Answer it true and you may pass.” He lowered his great head. “Who cut the first page?” Mihao opened his mouth and found nothing in it. “I don’t know,” he said at last. The lion studied him. “That is true,” he said, and stood aside. “For now.”

In the last chamber, on a bier of gold, lay a single page made of light. When Mihao lifted it, it folded itself small and slipped into his book, and for one moment he remembered a hand scratching behind his ears and a voice saying and then.

Then the floor shook. Somewhere above, the Hollow had smelled the leaf waking. Mihao ran, the queen’s laughter echoing behind him, and came up into moonlight with sand in his beard and a second page of his book filled in.