Last Breath - Rachel Caine - Paperback

The Morganville Vampires, book 11 of 15, completed series

Claire Danvers is concerned when three vampires vanish form Morganville without a trace. The last person seen with them is someone new to town, a mysterious individual named Magnus. Claire is convinced creepy Magnus isn't human, but is he a vampire, or something else entirely? 

Claire's hunt for answers leads her to solving another mystery that's long been puzzling her: why do vampires live so far out in a sunny desert when they're sensitive to sunlight? The answer has nothing to do with sunlight, but with water, and an ancient enemy who has finally found a way to invade the vampires' landlocked community. Vampires aren't the top predator on earth. There's something worse that preys on them, something much worse. Which means if Claire, and Morganville, want to live, they will have to fight on to the last breath.