Am I nuts or do flies know when you are planning to kill them? We get so many flies in the house this time of year... just now I was in the kitchen getting a snack and three flies were buzzing all round being annoying so I decided to get out the swatter. Lo and behold, as soon as I did so the flies disappeared! This is always happening to me! Are flies really that smart?? It's like they hide when you go get the swatter. I'm seriously starting to think they know you're trying to kill them!!