This really should be part of book one. It's just way too short. That's very annoying. Other than that, I'm very much enjoying the story. After reading the amazing Mountain Man series and being blown away by Callie I really wanted to spend more time with operators and experience the zombie apocalypse through them, and there just isn't anything out there that I had been exposed to that really does that. Enter this series; There are flaws, the writing has issues, the jumping around of characters is a bit jarring, but the terror and realism is there, and the way that I would imagine the apocalypse to really be is dialed in well. Granted, the explanation of why Britain is the last vestige of human survival and civilization doesn't make much sense to me, rather than Hawaii or other American Pacific territories, for example. And why the mainland United States falls and we Americans don't salvage portions of our own nation rather than abandoning our nation to move to the British isles. I think there is a major hole there and that bothers me, but, this is not my story, and I appreciate that the authors are telling a story I'm interested in being told to. I'm definitely moving forward with this series, which is another reason why I gave the book a full five stars. I typically would knock a star off when books are too short, pulling a cash grab, but I'm going to forgive it at this point in the series.