I think it might be. Even days after watching it, I drove my sister mad by being unable to sleep alone (and not even that alone; we had friends staying over, one was sharing a double bed with my sister, one was on a sofa on the other side of the bed, and I was in a sleeping bag by the door - all in the same room! - and I had to join the two in the bed because I was freaking out so much about zombies. Not my finest hour).