Book 5 opens with the combined strike force of Rangers, ODA-141 and the SEALs of Shark Platoon having an issue with reaching their objective.
A new character introduced in Book 4, Captain Nathan Harris, of the 2/75 Rangers has an issue with how ODA-141 wants to proceed with the mission.
Reaching way back to Book 1, the reader finds out what happened to Sergeant Stanislaus Luzetski and the remaining team members of Sierra 3. Just what have they been up to all this time?
Doctor Ronald Chambers, now safe at the DARPA facility deep in the Nevada desert, makes a discovery pertaining to why there are no wildlife scavenging the bodies of the dead in Las Vegas.
The addition of other survivors in other locations is touched upon. One group in particular are in the Hawaiian Islands and come up with a plan to escape the island chain and head for the west coast using an unconventional method of travel. Another group is introduced in the states and the reader learns what happened to them since the outbreak.
The book is broken down into different events occurring in different regions of the world depicting what's happening at roughly the same time as the combined strike team is attempting to reach their mission objective and finally discover who is responsible for unleashing hell on the world.