'I don't understand,' Marney said to her mentor. 'She's dead but still living?'

Denton nodded. 'The terracotta jar contained a spell, Marney, magic designed to turn a living person into a facile servant.'

'A golem, you said?'

'That's right ... eventually. At first, the spell acts like a virus that slowly destroys all humanity, driving its victim mad, giving them a hunger for blood –'

Betsy's scream pierced the corridor once again.

'– as you are now witnessing,' Denton added.

Marney shivered.

The old empath sighed. 'In the end, the spell will turn its victim's flesh and blood, hair and bone – all organic matter – into stone. It creates a slave, an abomination, neither alive nor dead, but stripped of all memory of whom they once were, and incapable of thought or reason – a golem, Marney.'

Marney looked at the body of Carrick floating in the tank. 'And the virus passes from victim to victim through saliva?'

'Or blood, I suppose.'

'Have you seen this kind of magic before, Denton?'

'No, but Hamir has experience of it.' The old empath was thoughtful for a moment. 'A golem has no other reason to exist than to serve the one whose magic created it. And trust me, Marney, whoever contained that spell in the terracotta jar has a far greater understanding of magic than we of the Relic Guild.'

Marney's eyes darted to her mentor. 'Spiral?'

'Or one of his Genii, yes – it seems likely.'

Marney bit her lower lip. It was no secret that Spiral loathed the denizens, and if he took control of the Labyrinth there would be no mercy for any of them. A magical virus such as this would spread like a plague if it escaped into Labrys Town, not just eradicating every denizen, but also turning each of them into golems: a million servants, all loyal to Spiral. And it could so easily have happened had the Relic Guild not contained the virus at Chaney's Den.

Marney frowned. 'But if this jar carried magic so powerful, how did Carrick smuggle it into the Labyrinth unnoticed?' She shrugged, with a casual smile she didn't really feel. 'The Genii can't reach us here. We're protected.'

'Nothing is infallible, Marney,' Denton replied. 'True, the Timewatcher's barrier prevents creatures of a higher magic entering the Labyrinth, but this was a spell that was well concealed within a small artefact. As for how Carrick managed to bring it here ... well, if I've learned anything it is that treasure hunters can be a resourceful lot, though I doubt Carrick ever really knew what he had found.' Denton sounded calm, but Marney could sense he was unconvinced when he added, 'The jar was probably a hopeful strike by the Genii.'

Marney stared through the window, past the gurney where Hamir, Gene and Angel were trying to save Betsy's humanity, to the tanks where the skeletons floated in preservative fluid.

'What about the Aelf and the alchemist?' she said. 'They weren't infected by this virus. Something else happened to them.'

'Hmm ...'

Denton twisted the fabric of his hat in his hands. Perplexed expressions were not often seen on the old empath's round face, and Marney was unsettled by the one that appeared there then.

Hamir's voice seeped through the wall of the quarantine room. 'We've failed,' he said. 'All we have done is encouraged the virus to take its full course.'

On the gurney, Betsy had ceased her struggles and screams, and now laid quite still and calm. She seemed to be staring up at the ceiling, though she no longer had eyes; just empty holes where they should have been. Her head was bald and lumpy, her face twisted into a grotesque mask. Even as Marney watched, the bargirl's limbs stretched and became painfully thin; her stomach shrank and her chest sank. The bite wound was gone, as were the black veins that snaked from it, and her skin was now the deep, clammy grey of soft stone.

She was a golem.

'What'll happen to her now?' Marney asked, but Denton didn't answer.

Gene removed his hood, took off his glasses, and pinched the bridge of his nose. His brow was beaded with sweat. Angel swore and also removed her hood. Her long black hair was streaked with moisture. Hamir, however, appeared as unaffected as ever. He looked at the two empaths standing in the corridor outside until the tint of the observation window darkened into a solid black rectangle in a cream wall decorated with tiny maze patterns.

'Poor Betsy,' Denton whispered in the following silence. 'I wonder if she had family.'

Marney tried not to think about that, but the idea was already in her head.

Thankfully, the moment was broken as the tall and broad figure of a young man strode down the corridor towards them. He was dressed in loose-fitting garb, his feet bare. His cane of green glass stabbed the floor with every step. Van Bam reached the empaths, his deep brown eyes showing concern.

'How is the girl?' he asked in deep, precise tones.

'Gone,' was all Denton said.

Van Bam nodded. His expression gave nothing away, and Marney refrained from reading his emotions.

'Gideon wants to see you,' he said to Denton, and then he looked at Marney with an apologetic expression. 'But not you.'

'Ah,' Denton said. He smiled lightly as he looked from Van Bam to his protégé. 'The Resident calls, and so I shall leave you two in each other's company.' He placed his crumpled hat on his head and set off down the corridor.

'Oh, Marney,' he called back. 'I'd not bother going to bed, if I were you. I suspect our day is only just beginning.'