This is a totally deadpan oral history of a global war against zombies that is allegedly going to happen in 5-10 years or so.
Brooks claims in the introduction that he as chief researcher for a UN research group measuring the costs of the war, and that this is a supplementary volume showing the human stories he encountered along the way as he interviewed people worldwide.
The book is structured to illustrate the development of the zombie problem, starting with small outbreaks in China through to the humanity's global fight to survive and eventual success. The story occurs half in the interviews and half in what they imply in the gaps.
Brooks has done an excellent job of capturing both the style of real oral histories, and creating interesting, often compelling, characters and stories. He lets a few jokes in here and there, but they're for the reader - as far as the narration goes, they are just straight facts of life.
As an aside, reading this made me aware of an important aspect of why I find zombies a fascinating horror genre. As I sat there thinking 'what would I do if that happened to me?' and realised that it is exactly that. The appeal of zombies is:
1. You can think about what you would do if it happened - tactics, tools, where you would go, etc.
2. It will never actually happen. NEVER.
Combined, those certainly make zombies a lot more fun to consider than (for example) climate change, major earthquakes or flu pandemics.