For the moment it will be sufficient that you step into this machine. If you would be so kind...”

With one glittering hand Valerius gestured to a metal sarcophagus, mounted in the side of the huge engine. A number of copper cables ran from it to the elemental spheres. A massive dais-mounted console was attached to it. Levers protruded from its sides. Ulrik hesitated.

Valerius said: “I did not pay ten thousand denarii just to do you harm. Please get in. We do not have all night. Surely you are not afraid...?”

The compulsions woven into the sorcerer’s voice took effect. Ulrik would not have his courage questioned by this perfumed popinjay even if he was in the man’s power. He strode towards the machine and lowered himself into it.

Valerius twisted a ring on his finger and the slave bracelet on Ulrik’s arm pulsed, holding him immobile, washed in a soft bath of euphoria. Despite all his efforts he was not capable of moving even his little finger. Valerius fastened leather straps across his chest and then pulled a lever on the side of the coffin. It swung into an upright position. Cogwheels on its side turned. Power crackled through the cables. The ozone stink increased.

Valerius twisted a knob on the dais in front of him. Brass needles slid from the nodes in the walls and pierced Ulrik’s skin. There was a soft sucking sensation as blood drained out into the clear tubing. A glowing sphere rose from the dais.

“There’s no need to worry, this is just a test,” said Valerius. “Despite what you may have heard about House Karnak we are not blood drinkers. Not all of us, anyway.”

He twisted his ring once again, and Ulrik found he could speak. “What are you doing?”

Valerius touched the sphere in front of him. Ectoplasm flowed from it, congealing into the floating figure of a man. It took Ulrik a few heartbeats to realise that the figure was himself. Valerius muttered something and made a gesture over the crystal sphere. It glowed and the figure changed, the outer skin becoming translucent.