Joe Ledger has some really rough patches in his past. You could say he has some scars on his psyche. He's kind of dealt with those psychic scars by becoming a bit of a badass. Okay, he's become the biggest and best badass there is. Good thing he's on the side of the angels, huh?
As Patient Zero opens, Joe is being forcibly recruited by a super-secret government agency called the DMS--the Department of Military Sciences. Run by a mysterious and apparently uber-powerful man called, usually, Mr. Church (a bigger badass, even, than Joe Ledger), the DMS is on the trail of the most horrifying terrorist plot never imagined: biological warfare in the form of a prion disease that creates perfect killing machines out of its victims.
Yes, zombies.
Patient Zero is more military/action thriller than horror novel, although the horror is pretty awesome (and gruesome). The action, though...the action is top-notch and unrelenting. The fast-paced narrative alternates between Joe Ledger's first person narrative, replete with many no-holds-barred battles, and third person narratives from the terrorists' perspective. More than once, after particularly disturbing terrorist chapters, I found myself muttering warnings to Ledger and the DMS through gritted teeth. That's effective storytelling.