Crisis Z e-bog

The day flew by, and I was sitting in my last class. I was in the middle of a test. There was silence, until a siren went off. We do a lot of drills here, one every week, so I know every single siren, but I didn't recognize this one. I sat so still, trying to figure out which one it was. Then I slowly found it familiar. I had heard about it on YouTube. It was a zombie siren. No, we're NOT in a zombie apocalypse. It was just weird, I mean the teachers always tell us, when a drill is going to go off, so we're prepared and aware. I looked at my teacher, and she was frozen, but she was slightly shaking too. And that was the moment I realized, that it wasn't a drill.