One

Distant screams rose in the night. He knew what that was all about. He shut his eyes tight to it, and thought only of his son.

The candle was out when he wakened. But it was only recently extinguished; he could smell its acrid last breath. He heard the scratching in the plaster between the walls. He sat up, his hand falling to the stock of the rifle, which filled his hand and gave him a surge of confidence. There was a shocking, high-pitched cry, so loud he thought the rat that had loosed it must be upon him. He swung his feet out of the sleeping bag and they landed, not on his boots, but on the greasy, bristling backs of countless squirming animals. They recoiled before he did; he jerked back onto the sofa and pointed the barrel of the gun at the floor. He fired. Something screamed. There was the sound of bodies, an avalanche of bodies, falling over one another to get away. But then he realised he'd hit something and they weren't trying to get away, they were fighting over the booty, they were tucking in.

Jane flipped over the back of the sofa. No light. No boots. Maybe a hundred, maybe two hundred rats in the room. Rats that he'd watched get fat and get thin again over the years, once the carrion ran out. Rats who had lost their timidity; he'd watched hunger push that right out of the rat set-up. Shit.

He leaned over the back of the sofa and snatched his rucksack towards him. He held it to his chest, and yelled out when a warm, bony body scuttled out of it, over his arm and away. A different rat might have buried its jaws in his throat.

There were three glowsticks in their wrappers tucked into an inner pocket. He tore two open and shook them awake: sudden acid-green light reflected back at him from dozens of eyes. More rats were pouring through a hole in the door beneath the desk. Fear turned him sluggish; his bladder slackened and he leaked piss. The sudden whiff of released chemicals sent the rats into a frenzy, but defocused them. Jane slammed the butt of the rifle into the window. A fist of wind did the rest of the work for him.

He felt claws at his feet and looked down as a rat attacked him, bared stained incisors shredding the leg of his denims. Its glistening fur seemed to ripple with pleasure as it inhaled the stink of his fear-sweat. Jane couldn't shake it off. Another rat got a piggyback off its mate and launched itself at his eyes. Jane twisted his face away so violently that he felt a muscle pull in his neck; blindly he swung an arm and batted the rat away. He beat at the rat on his foot with the butt of the rifle. The rat continued to gnash at the air even as it was stove in.

Jane got a leg out of the window and, straddling the frame, fired three shots into the room. A squeal suggested he'd hit something, enough time to get out while they fought over the remains. He stood on the windowsill, grateful it was too dark to see how far down he would fall if he lost his footing. To his left, below the edge of the sill, was a ledge that ran to the end of the building, a distance of less than ten feet. A drainpipe waited for him there: another twelve feet above that and he'd be on the roof.

He sat on the windowsill, hands on either side of him, and inched along, using his palms to lift his bottom and swing himself incrementally towards the end. The wind plucked at his clothes – it felt to Jane as though it were assessing his weight, gauging how much it would take to drag him off into the night. He paused at the end of the sill, thinking how best to make the drop. How far life could take you, he marvelled, how far away from what you deemed to be normal could you be transported. Cups of tea, the crossword, a phone call home, all of this seemed as bizarre in the same way as what he was doing now would have appeared to his old self.

He anchored his hands as best he could to the windowsill and lowered himself towards the ledge. Almost immediately his muscles began to tremble. The breath hammered out of him; he was going to fall. But then his foot found concrete and he leant his weight upon it. The surface felt about as solid as a pack of muscovado sugar. He sidestepped as quickly as he dared to the end of the building, his hands flat against the wall by his sides, creeping along, giving him the illusion of control.

There was a hiss; rats were pouring like oil onto the window sill, sinuous, jet, intent. He grappled with the drainpipe, feeling his hold on the rifle slipping. As he reached around to secure the strap on his shoulder he felt the drainpipe lurch towards him. A great chunk of stone containing the screws that attached the top section of pipe to the masonry had come free, weakened by the corrosive drizzle. Jane shrugged the backpack from his shoulder and let it fall. He looped the strap of the gun around his neck and scrambled up the pipe until he felt close enough to grab the edge of the roof, but his fingers were a couple of inches shy.