In time, the vegetation began to thin and sprouted closer to ground level again. Janer saw Pland pointing at something, and it took him a moment to distinguish, amid the surrounding trunks, what he was indicating. It was an octagonal metal post, half a metre wide and higher than a man, its surface thick with grey corrosion.

‘We’re closer than I thought,’ said Ron.

Janer glanced at him, then at Forlam who was now showing some interest, and staring at the metal post. ‘Perimeter,’ the crewman managed to utter.

‘What is it?’ asked Janer, puzzled.

‘Slave post,’ said Ambel.

Janer was still none the wiser, but he saw Erlin nodding in understanding. Before he could ask her what Ambel was talking about, the Captain led them out of the dingle, and she had moved back to escort Forlam.

They came out on to the crest of a hill sloping down to a valley. Below them, a river rumbled between red-brown boulders. On the other side of this stood structures built of the same stone: tall many-windowed buildings sprawled like a disjointed medieval fort. Crenellated walls stretched between them and there were signs, under thick vegetation, of what had once been a moat. To one side the ground had been levelled, and the vegetation there was having trouble getting a hold on the glassy surface. A wrecked landing craft of very old design stood decaying on that same surface.

Janer moved up beside Ambel and stared.

‘Hoophold,’ said the Captain.

‘And those posts?’ Janer queried, gesturing behind with his thumb.

‘The posts broadcast a signal to activate the explosive collars his captives and slaves wore. Here was where he kept them imprisoned, then cored them, and from here he shipped them out to the Prador,’ Ambel explained.

‘You think that . . . the Skinner has come back here?’ Janer said.

‘I don’t have to think,’ said Ambel, and pointed.

Squatting on a merlon of the nearest stretch of wall was something that could have been taken for a gargoyle - until it shifted its position and briefly opened its stubby wings. The head of Spatterjay Hoop was watching them approach.

* * * *

It all came down to Prador politics, the Warden realized now. It continued observing through the many eyes of the enforcer drones below, and saw the ships of the Convocation fleet moving towards the Skinner’s Island, and far ahead of them the ship Frisk had seized. Of course: Ebulan wanted all living witnesses dead so he could claw back power in the Third Kingdom. One large explosion, when that fleet reached the island, and all the Prador’s problems, here at least, would be solved.

‘SM Twelve, I want four enforcers to get between the main fleet and that ship. If it shows any sign of moving from its present location I want it destroyed.’