For years the Department of Military Sciences has fought to stop terrorists from using radical bioweapons—designer plagues, weaponized pathogens, genetically modified viruses, and even the zombie plague that first brought Ledger into the DMS. These terrible weapons have been locked away in the world's most secure facility. Until now. Joe Ledger and Echo Team are scrambled when a highly elite team of killers breaks the unbreakable security and steals the world's most dangerous weapons. Within days there are outbreaks of mass slaughter and murderous insanity across the American heartland. Can Joe Ledger stop a brilliant and devious master criminal from turning the Land of the Free into a land of the dead?

Code Zero, a Joe Ledger novel from Jonathan Maberry, is the exciting direct sequel to Patient Zero.