Darkfever

I'm hooked. This begins with a murder: the protagonist gets the call that her sister has died in Dublin. She goes to Ireland, unsatisfied with the lack of answers... and stumbles into a huge conflict of the Fae, discovering shocking things about herself and her sister as she unwillingly takes her place in this huge otherworldly situation. She is under the guidance of Jericho Barrons, who seems to be on her side, but he's mysterious and enigmatic. I still can't tell. Picking up the next book immediately!