The Smith family, and the few stalwarts of the Wolf Squadron, continue their campaign to reclaim the Atlantic Ocean from the zombified humans one ship at a time. So far they have pulled a few hundred people from small ships and lifeboats. Then the difficulty of rescuing those trapped on a superliner cruise ship compels what remains of the USA's government to take action. They authorize a submarine to provide necessary equipment and in the process reveal that they have been shadowing the ragtag fleet for a few weeks. The survival of a few submarines is good news, but they have an ulterior motive. Without a vaccine the thousands of crew members on those subs will die. 

The vaccine issue is a tricky one. Everyone knows the highly illegal methods used to manufacture a viable vaccine before the fall of civilization. In return for admitting that one of the family actually participated in the lab process, and could recreate it with adequate equipment, the USA agrees to officially pardon how that knowledge was acquired. Additionally, they offer field commissions to those working in the rescue effort with Smith himself being made the highest ranking officer of the US Navy. It's almost necessary because the first thing they want is for the fleet to rescue any survivors on the USS Iwo Jima. Hopefully there are enough surviving crew and ammo for the squadron to take back Gitmo which hopefully has the equipment and supplies they need to manufacture a vaccine. At this point the government isn't going to quibble about the questionable morality behind that vaccine.

The heroism of the USA's armed forces is lauded here, most especially that of the USMC, but Ringo continues to break up the combat with what the characters refer to as zambies, or Zombie Apocalypse Moments. For each major rescue Ringo first relates the experiences of those trapped. Some are funny, some pose difficult ethical questions, and all of them are sad. Insane coping mechanisms are starting to show up among the survivors and of course some people are just outright insane. Overall there is still plenty of adventure and entertainment making this second book a worthy successor to Under a Graveyard Sky.