True Blood is a HBO tv series based on the Southern Vampire Series (or the Sookie Stackhouse Novels as most call them) written by Charlaine Harris.
The show/novels are set in a world where vampires have come "out of the coffin" and exposed themselves to the public, creating an uproar and an entirely new form of prejudice from regular people who fear and hate them.
Because it is a HBO drama, the show is EXTREMELY graphic and much more "adult" than your average vampire tv show. Also, don't tune in expecting 'Twilight' vampires because these vamps are REAL "vampires" they are dark, duplicitous and manipulative, even though some appear to be (and are) very nice.