Uther Doul sat on the bed in Bellis’ cell. The room was still sparse, though the surfaces were now piled with a few accoutrements he had had brought from her rooms: her notebooks, a few clothes.

He watched her as she turned the grindylow statue in her hands. She ran her fingers over it carefully, curiously, feeling the intricacies of its carving. She stared at its twisted face, and into its mouth.

"Be careful," Doul advised her as she touched her nail to one of its teeth. "It’s dangerous."

"This is… the cause of it all?" said Bellis.

Doul nodded. "He carried it with him. He used it to kill several men. He folded space with it, performed thaumaturgy I’d never seen. That must be how he got into the compass factory."

Bellis nodded. She understood that Doul was talking about the means by which Fennec had allowed New Crobuzon to find Armada. Some secret engine, some mechanism.

"It must be safe now," Doul went on. "The lodestone must have been on their Morning Walker."

Probably, thought Bellis. A device that tracked Armada. You’d better hope it’s not languishing on one of those ironclads, drifting all sunbaked and pocked, stinking by now with its dead crew, where maybe it could be found one day. She turned the statue over again and studied it closely.

"From what we can tell…" Doul continued slowly, "from what we’ve got out of Fennec, this statue is not the main thing. Just as the point of a gun isn’t the gun but the bullet, so with this: it’s not the statue itself that has the puissance. That’s just a conduit. This," he said, "is the source of the power."

Doul tickled the tough, thin strip of flesh embedded in the statue’s back.

"This is the fin of some ancestor, some assassin-priest, some thaumaturge, some magus. Housed in stone, in a shape that mimics its original form. This is a grindylow relic," said Doul, "the remnant of some… saint. That’s what stinks of power.

"That’s what Fennec told us," he said, and Bellis could imagine the techniques by which Fennec had been made to answer those questions.

"This is what’s behind it all," said Bellis, and Doul nodded.

"It did amazing things. It allowed Fennec to do amazing things. But even so, I think he’d only just begun to understand it. I think New Crobuzon must have reason to believe that this… this charmed debris has far more power than Fennec had learnt to use." He looked Bellis in the eye. "I don’t think New Crobuzon would come so far, try so hard, for anything less than the most powerful forces."

Bellis looked reverentially at the object in her hands.

"We have our hands," Doul said quietly, "on something extraordinary. We have found a very great thing. Gods know what it might allow us to do."