It was easy to follow Elias and Saleh. But when he found them again Anubis retreated into the shadows. They stood by an abandoned yard with a faded sign over it, and seemed to be speaking to thin air. The smell, however, was familiar, and strong: the same smell from the downed ship, the same as inside the cave.

“I wouldn’t go . . . in there,” he growled. But the boys didn’t hear him or, if they did, they paid no attention.

Anubis watched them go in. He fell asleep, and when he woke he felt a hand brush through his fur and he shivered, for there was no one there, and a voice in his mind said, mockingly, Nice doggy.

Then it was gone, the smell and the voice. When Saleh came out alone, Anubis said, “I tried to . . . warn you.”

They walked together to the harbour. The sun was very bright and the gulls cried in the distance, and Anubis smelled the sea and thought of distant shores.

“Where to, then?” he said.

The boy stared across the water.

He said, “Neom.”

So they got on a ship and went there.

11. The Shelter

The robot passed the intersection of Ansari and Khayyam and came to the Square of Future Prosperity, where pigeons congregated around the large Statue of the Unknown Scientist. The robot bought a packet of sunflower seeds from a woman who sold them from a kiosk, and it opened the packet and scattered the seeds on the grass and the pigeons came and pecked at the robot’s feet.

Nannies went past pushing their charges. Small children played in a sand pit. An elderly couple, clearly tourists from some other, less youthful place, came and sat on a bench and watched the children play. Sprinklers whoosh-whooshed water over the manicured grass. The robot stood perfectly still. The sun was high in the sky but a cool breeze blew through that small city square from hidden air conditioners.

“Hey, mister,” a small child said. The robot turned and looked down at the little human.

“Yes?” it said.

“Are you a spaceman?”

The robot gave it some consideration.

“I am not a man,” it said. “But I have been to space.”

“What’s it like, mister?”

“Space?” the robot said. “It smells like hot metal and grilled lamb and sulfur. Both sweet and metallic. Or so I’m told. I cannot smell.”

“You’re funny,” the child said. Then she waddled away.

The robot crumpled the empty packet of seeds in its hand and put it into a waste bin provided. Then it left the square. It followed the exit signs and made its way farther along the road until the shiny new buildings gave way to the older structures of the Nineveh Quarter, and people’s clothes took on a secondhand quality. Butchers sold diced mutton and goat, a four-armed preacher standing on a produce box entreated the passersby to seek salvation in the zero-point field.