Zombies
This was one of those dreams where the dream world seemed to be half way between a video game and reality.
I was in Cambridge city centre, in the Grafton Centre, and we were playing a game about being zombies. If you were a zombie you had to find one of the humans and kill them and then they would become a zombie. If you were a human your job was basically to survive, and every time you killed a zombie they would respawn a bit further away and come hunting for you again.
Initially I think I was on the human team, but at some point I got stabbed by a zombie which meant that he respawned on the human team and I was turned into a zombie in his place. I don't remember much of the original battle, but at some point all of the humans had submachine guns, and then somehow I got one of them off of the humans and was using it to kill whole groups of them.
The last part of the dream that I remember was being back at home. I was still playing the game and I was still a zombie, and there was another person who was on the human team in my house. For some reason I felt that I couldn't risk attacking him there so I left the house and started roaming the streets looking for my next victim. I grabbed a weapon on my way out, but because I was avoiding the other guy I ended up just grabbing the first thing I could find which was a paring knife from the kitchen.
When I was walking around it was a nice sunny day and there were lots of people about. I remember seeing people in their front gardens mowing their lawns, and another guy getting things out of his garage. I was holding the paring knife and thinking about which one of the unsuspecting people I was going to stab so that they could take my place as a zombie and I could be human and stop playing. I started to wonder about the game, and if it was OK to play with people that weren't really playing. Then I started to wonder if stabbing them would even work in the game world, or if it would kill them in real life. I was starting to get nervous about doing it, but I really didn't want to be a zombie any more.
At that point the man who was in my house came walking past. The was marching quickly and talking to himself about how he was going to kill all of the zombies. The last thing I remember is running towards him to try and kill him.