“What is it, Hummingbird?” Nasir muttered. He looked at the instruments again. They were not making any sense.

“Who are you talking to, Nasir?” Laila said. She looked at him strangely.

“It’s the worms,” Nasir said. “The worms are moving.”

“What worms?” Laila said. “There shouldn’t be any—watch out!”

A giant UXO blocked their path. Nasir swerved, Hummingbird chattered in agitation and Laila cursed as the car hit a dune and came to a hard stop.

“Where did that come from?” Nasir said.

Laila took over the instruments.

“They’re everywhere,” she said.

“This isn’t supposed to happen,” Nasir said uselessly.

“I told you I felt something,” Laila said.

“What’s spooked them so bad?” Nasir said. But he had a nasty suspicion already. He stepped out of the car and Laila followed.

“Hey, you!” Nasir shouted.

The giant UXO was built like a—

Nasir stared.

Most UXOs were just boxy tank-like machines or diggers. This thing was a. . . .

It looked like a sort of giant humanoid robot.

It was a very old mecha, its shell the colour of the sand. It almost vanished against the landscape. Then you realised its outline and how big it really was and you were. . . .

Afraid.

It towered over them, and its head turned and it saw them.

“What?” the mecha said.

“Where did that come from,” Laila muttered.

“I heard that!” the mecha said. “Rude.”

“Sorry,” Laila said. “Didn’t mean . . . I mean. . . . Where did you come from, though?”

“The desert,” the mecha said.

“How long have you been in the desert?” Nasir said. In all his time patrolling, he’d never seen a mecha.

“Dunno,” the giant robot said. “My internal clock stopped working. Centuries maybe. Years. It doesn’t matter.”

“What did you do all that time?” Laila said.

“Not much. Thought about stuff. Dreamed.”

“Do robots dream?” Nasir said, before he could stop himself.

“You’d be surprised,” the robot said. “Also, an old Webster taught me sand drawing, so I’ve been doing a bit of that. It is an ancient art, you know.”

“I didn’t . . .” Nasir mumbled.

“We never saw you before,” Laila said.

“No, well,” the mecha said. “I saw you. You’re always buzzing about, aren’t you. Don’t have much call for humans, myself. Not since the war. I had some friends but they went off-Earth and left me. Don’t blame them. Too big to go to the Up and Out in this form. I could have transferred my consciousness into something smaller, I suppose. But then this is who I am. Name’s Esau, by the way. How do you do.”

“How do you do!” Nasir said wildly. He exchanged a bewildered glance with Laila. Behind Esau, he saw, came other UXOs, emerging out of the sands like ghosts, marching in union—

Towards the city, Nasir realised with alarm.

They were heading to Neom.