Step into the shadows with the first of a series that blends deduction with suspense... and blood. Dru is not a commonplace vampire - he's The Inquisitor, chosen by the elders of a most sanguine and secret society. His role is to investigate sedition and punish treason among the undead, of whom there are clans, factions, and territories. He's made enemies over the centuries. He's dealt with many of them using the help of myriad assistants, including gargoyle spies. But now a mysterious force has broken one of the cardinal rules governing vampire society. The first signs that something is wrong are small. They go unnoticed in the elegant clubs and refined circles inhabited by the vampire elite. But in the underbelly of the undead world, in those locations only certain humans and vampires can be found, there are those who notice. The danger is real and it is coming. A terrible threat that could lead to complete madness unleashed on an unsuspecting world causes Dru to embark on an epic journey. From the posh clubs of Philadelphia to hidden monasteries in the Alps, lines are being drawn and Dru's fortitude will be tested as he discovers the meaning behind A Warning in Blood.