Begins exactly where the Second Season ended, with vampire Bill Compton asking Sookie Stackhouse to marry him. But he's kidnapped by what seems like a gang of thugs. We soon learn they are werewolves who are addicted to vampire blood. When we see them transform they are real wolves with glowing eyes. There are flashbacks to Erick Norseman's past and we learn he saw these same werewolves back in World War II. Werewolves which are working for a vampire. It's this very same vampire that killed Eric's parents a thousand years earlier and he's always wanted revenge. Once he discovers who that vampire is, he puts his revenge in motion.
Sookie's brother, Jason, falls in love with a poor white trash girl whose family/relatives can transform into panthers. And Sam Merlotte is reunited with his biological family--and they are trouble! By the end of the season we discover that Sam isn't as innocent as depicted in the previous two seasons. He has definitely done some bad things. The most important revelation, however, is what type of creature Sookie turns out to be. This is the reason why vampires are so attracted to her.
Although this is one of my favorite current series on television I didn't find it quite as engaging as Season Two, which was the best so far.