Gabriel Tempest is an orphan, a criminal prosecutor and a vampire. Tempest deviates from Bram Stoker's tale of Gothic horror and moves towards a tale of inner conflict.
All the typical vampire limitations were created so that vampires could hide in plain site. Gabriel's main problem is that to survive he has to take a life every fourteen days, which makes him worse than any murderer he has ever prosecuted. To deal with the guilt, he vows to only kill those who he deems have forfeited their right to continue among the land of the living.
If that wasn't a big enough headache, there is also the belief that Gabriel is the last living descendant of Vlad the Impaler, the first vampire. That wouldn't be a problem if there wasn't a prophecy which makes it clear that The Impaler's last descendant would rule all of the vampires after a great war.
Gabriel has to contend with his new eating habits, and getting away with being New York City's newest serial killer, while avoiding other vampires who want him dead. All of this while still performing his duties as a criminal prosecutor would make anyone a little nuts.