Phantom Prey book by John Sandford

A widow comes home to her large house in a wealthy, exclusive suburb to find blood on the walls, no body - and her college-age daughter missing. She's always known that her daughter ran with a bad bunch. What did she call them - Goths? Freaks is more like it, running around with all that makeup and black clothing, listening to that awful music, so attracted to death. And now this.
But the police can't find the girl, alive or dead, and the widow truly panics. There's someone she knows, a surgeon named Weather Davenport, whose husband is a big deal with the police, and she implores. Weather to get her husband directly involved. Lucas gets in only reluctantly - but then, when a second Goth is slashed to death in Minneapolis, he starts working it hard. The clues don't seem to add up, though. And then there's the young Goth who keeps appearing and disappearing: Who is she? Where does she come from, and more important, where does she vanish to? And why does Lucas keep getting the sneaking suspicion that something else is going on here ... something very, very bad indeed?