Harry, of course, is immediately clued in that the woman is a lycanthrope (werewolf in common parlance, though they never use that word in the episode and, if I recall correctly, Butcher never used that word in Fool Moon, either). The FBI moves in and takes the case over, pushing Murphy and Dresden both out of the way and threatening Dresden with jail time.
Dresden doesn't drop the case, though, because if he did we wouldn't have a show. Instead he focuses on the victim's roommate, Heather, and is able to put the pieces together as to what happened to her. But there's a twist he's not aware of--the hostile female FBI agent is also a lycanthrope, and her partner is killing lycanthropes in order to cure her of her affliction. Unfortunately, he's been bitten, too, as we saw in the teaser.
It seems like this would have been a much better pilot episode than "Birds of a Feather." Everybody has a general knowledge of werewolves, which would have made the story easily accessible to viewers unfamiliar with Dresden. In addition, this plot was largely adapted from Fool Moon, so it might have pleased established Dresden fans a bit better, as well. There's not quite as much background exposition in this episode as there was in "Birds of a Feather", but in this case I think that's a good thing, since the exposition in "Birds of a Feather" seemed to me to be more confusing than helpful.
In any case, this was a much stronger episode than the last two, with some genuine creepiness and strong emotion, and I hope the show continues with this trend.