“People are approaching,” he said urgently, “across the roof.” With practised movements, he plucked his whip from his belt. His long knife seemed to dance into his left hand and pose, glinting in the refracted sodium lights. He had become a warrior and a hunter again.

Isaac stood and drew his flintlock. He checked hurriedly that it was clean and he filled the pan with powder, trying to shield it from the rain. He felt for his little pouch of bullets and his powder horn. His heart, he realized, was beating only very slightly faster.

He saw Derkhan readying herself. She drew her two pistols and checked them, her eyes cold.

On the roof’s plateau, forty feet below, a little troop of dark-uniformed figures had appeared. They ran nervously between the outcroppings of architecture, their pikes and rifles rattling. There were perhaps twelve of them, their faces invisible behind their sheer reflective helmets, their segmented armour flapping against them, subtle insignia displaying rank. They spread out, came at the gradient of roofs from different angles.

“Oh dear Jabber,” swallowed Isaac. “We’re fucked.”

Five minutes, he thought in despair. That’s all we need. The fucking moths won’t resist this, they’re coming here already, couldn’t you have taken a little longer?

The dirigibles still prowled closer and closer, sluggish and ineluctable.

The militia had reached the outer edges of the tumbling slate hill. They began to climb, keeping low, ducking behind chimney stacks and dormer windows. Isaac stepped back from the edge, keeping them out of sight.

The Weaver was tracing its index finger through the water on the roof, leaving a trail of scorched dry stone, drawing patterns and pictures of flowers, whispering to itself. Andrej’s body spasmed as the current rocked him. His eyes wavered unnervingly.

“Fuck!” shouted Isaac, in despair and rage.

“Shut up and fight,” hissed Derkhan. She lay down and peered carefully over the edge of the roof. The highly trained militia were frighteningly close. She aimed and fired with her left hand.

There was a snapping explosion that seemed muffled by the rain. The closest officer, who had scaled nearly halfway up the slope, staggered back as the ball struck his armoured breast and ricocheted into the darkness. He teetered momentarily on the edge of his little roof-step, managed to right himself. As he relaxed and stepped forward, Derkhan fired her other gun.

The officer’s faceplate shattered in an explosion of bloody mirror. A cloud of flesh burst from the back of his skull. His face was momentarily visible, a shocked gaze embedded with slivers of reflecting glass, blooming with blood from a hole below his right eye. He seemed to leap out backwards like a champion diver, sailing elegantly twenty feet to crack loudly against the base of the roof.