Zero Days

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There’s a reason they use it in war zones.At five foot two I couldn’t quite reach to pull myself up, so I scaled a nearby tree with a sturdy branch overhanging the car park, lowered myself until my feet made contact with the top of the wall, and then ran softly along it to a place where I could drop down out of sight of the CCTV cameras that circled the building at intervals.On the other side of the car park was the fire door Gabe had described, and it looked promising. A standard half-glazed door with a horizontal release bar on the inside. I saw with satisfaction that it was poorly fitted, with a gap at the bottom that you could practically get your hand through. It was the work of about thirty seconds to slip my long metal slider underneath, swing it up so the hook caught on the bar, and pull firmly down. The door opened and I held my breath, waiting for the alarm—fire doors are always risky like that—but none came.Inside, the lights flicked on automatically—big fluorescent squares in a tiled ceiling that stretched away into the darkness like a chessboard. The far end of the corridor was still pitch-black, the sensors there not yet picking up my movement, but the section I was in was bright as day, and I stood, letting my eyes adjust to the glare.Lights are a bit of a double-edged sword. On the one hand, they’re a huge red flag to anyone monitoring the security cameras. There’s nothing like a screen lighting up like Christmas to catch a security guard’s eye and make them glance up from their phone. But you can sometimes style it out if you’re caught walking confidently around a building at night when the lights are on. It’s much harder to explain your presence if you’re creeping along an unlit corridor with a torch. You might as well be wearing a striped T-shirt and carrying a bag marked Loot.Right now it was 10:20 p.m. and I was wearing my “office” clothes—black trousers which looked like they could be the bottom half of a suit but were actually stretchier and more breathable than any regular office wear, a dark blue blouse, and a black blazer that was standard, off-the-rack from Gap. On my feet were black Converse, and I had a gray Fjällräven backpack slung over my shoulder.Only my hair was out of place. This month it was dyed a fluorescent scarlet that wasn’t close to any natural shade and didn’t really fit in with the slightly stuffy atmosphere of this company—an insurance group called Arden Alliance. Gabe had suggested a wig, but wigs were always a risk, and besides, I was getting into character. Jen—I had decided my imaginary office worker was called Jen—worked in customer services but had fond memories of her gap year after university and still thought she was a little bit cool. Jen might have buckled down to achieve promotion, but her hair was the last flicker of a personality she hadn’t quite abandoned to the nine-to-five. That, and perhaps a touch too much liquid eyeliner, plus a tattoo on her shoulder blade that said stick ’em with the pointy end.The eyeliner was real—I didn’t feel properly dressed without a smooth flick of Nyx Epic Ink. The university degree was imaginary. So was the tattoo. I wasn’t sufficiently into Game of Thrones to ink it, though admittedly if I had been, Arya was the best character.Jen had been working late, lost track of time, and was heading hurriedly home for the weekend. Hence the comfortable shoes. The backpack was for her office heels—although that was where my role play broke down. Jen might keep heels in her backpack. Mine was full of housebreaking tools and computer equipment loaded with some deeply shady software Gabe had downloaded from the dark web.I walked softly down the corridor, my rubber soles silent on the carpet, trying to look as though I belonged here. On either side were the doors of empty offices, just the occasional LED glowing in the darkness where people had failed to turn their computers off properly for the weekend.A photocopier in an alcove blinked hypnotically and I stopped, glancing up and down the hallway. It was illuminated behind me but dark around the corner up ahead, the motion sensors not yet detecting my presence. So much the better—the lights might alert security, but that worked both ways. The guards were unlikely to be coming from behind me; that corridor was a dead end out to the car park. If they came from up ahead, the lights flickering on would give me enough warning to double back or duck into one of the offices. Gabe would probably tell me to get on with finding the server room—but the chance was too good to miss.Behind the copier were, as I’d hoped, a tangle of wires and two LAN ports for hooking up devices to the main company network. One was in use, connected to the copier. The other was empty. Heart beating, I glanced up and down the corridor and took one of the little Raspberry Pi computers out of my backpack.The Pi was smaller than a paperback book, and I