Inside the decrepit building on the east side of Labrys Town, Samuel was a few steps ahead of Bryant and Macy.

He faced a hallway, long and wide, home to twelve apartments, six on each side. The door of every apartment was open or smashed from its hinges. Above, light prisms ran in a straight line down the centre of the ceiling, every one broken and useless. From the doorways to the left, ghostly shafts of pale sunshine penetrated into the hallway. Dust drifted and twinkled. The shafts of sunlight dimly lit the way ahead, down to the end and the closed door of the stairwell. Everything appeared dreary grey through the lenses of Samuel's magically enhanced goggles.

'What's your magic telling you?' said Macy.

Samuel's prescient awareness was warm inside him, as though it had one eye open, drowsy but not asleep. The noise of Bryant breaking open the entrance doors had not alerted anyone in the building. All was still and quiet, but ... 'There's something here,' Samuel said.

'What's that smell?' Bryant asked.

The building reeked of decay.

'Fabian Moor's virus,' Samuel said, his gut knotting. 'It's the smell of his victims.'

Bryant scoffed, unimpressed. 'Golems smell like rotting vegetables?'

'No.' Samuel's voice was low and sombre. 'But the infected do.' Gripping his revolver tightly, he turned to the twins. 'When they come for us – and they will come – be ready. The infected have no fear of what you can do to them. They'll only be interested in your blood. If you get bitten, there's no cure for Fabian Moor's virus. Remember that, and put them down quickly.'

'Okay then,' Macy said offhandedly, and she gestured to the hallway. 'I guess you're up.'

Samuel bristled. He could sense that Macy and Bryant's faces, hidden within the shadows of their charmed hoods, still carried arrogantly confident expressions, despite the warning.

'Stay behind me,' he said. 'Don't get in my way.'

Guided by the warmth of his magic, Samuel slowly moved down the hallway, revolver in hand.

The agents' footsteps rustled upon the threadbare carpet, kicking up puffs of dust as though they walked upon sun-baked dirt. The dingy grey paint on the walls was peeling into brittle flakes, and the plaster beneath looked ready to disintegrate into fine powder at the slightest touch. There was an unnatural ambience in the apartment block, a distant white noise that seemed to absorb sound into a lifeless hum, as if the building itself was dying. Dry and crumbling, it was as if this place had been abandoned for years.

When he stepped in line with the first set of opposing apartment doors, Samuel stopped and waited for his prescient awareness to detect any danger in the immediate future. It remained dull and drowsy within him. He gestured for the twins to check the apartment on his right, while he investigated the left.

He was greeted by a miserable one-room dwelling, small and cramped and scarcely habitable. There were no ornaments or personal flourishes, and the only furniture was a single bed and a rickety looking table. Both had been broken, and the mattress had been shredded. Dried blood spattered the carpet and a tangle of stained sheets. A thin layer of dust coated everything.

Samuel frowned when he turned to the tiny kitchen in one corner of the room. The oven had been vandalised. Its door lay on the floor. Its parts and internal workings had been ripped out. On closer inspection, Samuel saw the metal insulation box which held the oven's small power stone had been cracked open, and the stone itself was missing.

Back out in the Hallway, Bryant informed Samuel that he and his sister had found the same aftermath of violence in the other apartment, but no denizens, dead or otherwise.

'Is the oven broken?' Samuel said, and Bryant nodded. 'Is the power stone missing?'

Macy ducked back inside to check, and confirmed it was gone.

'What does that mean?'

Without reply, Samuel led the group to the next set of apartments, and then the next, and the next. In each, furniture had been smashed, blood had been split, and the power stones had been removed from vandalised ovens.

Three-quarters of the way down the corridor, Samuel looked up through a hole that had been cut into the ceiling. It was neat and circular, leading to the next floor, and large enough for him to pass through.

'Quicker than using the stairs, I suppose,' Macy half-joked.

'What's that noise?' Bryant said.

Samuel was aware of it too. A tapping – no, patting, dull and fleshy.

His magic grew a little warmer.

Leading with his revolver, Samuel stepped away from the hole in the ceiling and checked the next set of apartments. They were the same as the others, as was the last room on the right; but the last door on the left was closed. The stench of rotting vegetables was stronger, the patting louder.

Samuel pushed the door open with the barrel of his gun. He looked into a communal bathroom and found two people inside.

One, an old man lying on the floor, was already dead, his clothes shredded. A woman crouched over him, so emaciated by the Genii virus her age could not be determined. Her head was bald, her skin clammy grey and streaked with black veins. With one hand, she reached into a gaping wound in the man's stomach, pulling out stringy lengths of innards and stuffing them into her mouth. With the other hand, she rhythmically smacked the man's broken and blood-smeared face as if her need for violence had formed a nervous tick.

Pat, pat, pat ...

Macy and Bryant moved up behind Samuel. Macy swore. Bryant gagged.

The infected woman stopped feeding upon the dead man and looked sharply at the doorway. Her jaundiced eyes were full of the purest hate. Blood and morsels of human flesh spattered from her mouth as she gave a series of shouts, a mixture of coughing and barking.

Samuel's revolver flashed and made a low and hollow spitting sound. The woman's head jerked back. The bathroom tiles cracked behind her in a spray of blood. She slumped forward over the old man's body, and Samuel lowered his gun. He closed the bathroom door and turned to the twins.

They stood uncertainly. Perhaps the message had finally sunk in; perhaps now they understood why Gideon had given them the order to show zero tolerance to any denizen carrying infection—

Time dulled . . .

The environment pressed in on Samuel's senses like needles. The warmth of his prescient awareness flared to a fiery scream carried on his blood, drawing his eyes and the aim of his weapon to the hole in the corridor ceiling. He felt shifts in the atmosphere, imperceptible to the others, and he knew what was coming before he heard the shuffling of quick footsteps from the floor above.

'Get ready,' he said, and the twins wheeled around, standing before their fellow agent.