It's always darkest before dawn. Secret government unit Department 19 is recovering from evil vampire Valeri Rusmanov's deadly attack on their base. The Department's newest member, teenage operator Jamie Carpenter, is tasked with training up a new squad, as his friends and colleagues desperately search for ways to try to stop what is coming. The timing couldn't be worse for a coordinated, global attack on a number of maximum security prisons and hospitals - with the already-dangerous inmates now on the loose and turned into vampires. One of the escapees has a deep connection to one of the darkest moments in the history of Department 19 and embarks on a quest that threatens to expose the existence of vampires to the public. And with each day that passes, the regenerated Dracula gets stronger, bringing Zero Hour closer. In this third installment of the epic Department 19 series, Will Hill delivers higher - and sharper - stakes than ever before.