“Too fucking right I’m holing up here,” Bran said. “Have you not heard the troopers? In the Highlands they’re already burning witches.” He looked at Ted, calculating. “I didn’t mean it. The Egress Hatch thing. I mean, I did. And I was right, wasn’t I?” He glared at Blue. “It did come from space.”

Blue rubbed his neck, through the thick fabric of his suit. “It is possible.”

“That mirror thing the Moonseed is building. It’s a solar sail,” Bran said. He smiled. “It’s obvious.”

Ted turned to Blue. “A what?”

Blue was wheezing; maybe the concentrated dust here was getting to him. He said, “A sail, to catch the sunlight and so drive a spacecraft. Perhaps that’s the purpose of the large parabolic structure the Moonseed is struggling to assemble. Others have speculated like this. The Moonseed seems to be making spaceship parts. But it is stranded, here, at the bottom of this gravity well, under all this air.”

Spaceship parts. For a few seconds, the strangeness of the thought threatened to overwhelm Ted.

“Stuck at the bottom of a well.” Ted frowned at Blue. “You sound as if you feel sorry for it.”

Blue looked up. “In a way. After all, it’s possible it means us no harm.”

“I was right,” Bran said, as if crooning. “I knew I was right. But I went a little crazy. And then, as soon as the ground started to give way—”

“You had your fun,” Ted said evenly. “Money. The girls. Didn’t you? And it cost my boy his life.”

“Are you another witch-burner, old man?”

“I don’t know. I haven’t decided.”

That seemed to renew Bran’s fear. He looked in desperation at Blue. “Who the fuck are you? Can’t you stop him?”

“I am a scientist,” Blue said. “I am here to study the Moonseed. That is all.”

Bran searched Ted’s face, his eyes huge in the dark, his face thin and weak.

“Story time’s over, laddie,” Ted said softly.

There was noise outside: whistles, shouting.

Blue looked out into the main body of the Cathedral. “I think the light is changing,” he said.

Bran tried to wriggle from Ted’s grasp. “What does that mean?”

“It means,” said Blue, “we should get out of here.”

A sound like gun-fire. Deep-throated coughs.

“Now,” Blue said.

Bran seemed dazzled by the daylight. Perhaps he hadn’t been outside for days, Ted thought. With his hand still clamped on Bran’s collar, he looked around.

A party of soldiers was running, to the west, away from Arthur’s Seat, jumping over rubble. One of them looked hurt; his mates were helping him hobble along. When they saw Ted and Blue they waved. Come on.

Smoke was rising from among the ruins atop Calton Hill.