Gruesome murders begin to pop up in River County, and Rune is introduced to the bird shifters - to one bird in particular, a woman named Cree Stark. When she gets a whiff of the shifters' scents where COS had been executing a grisly sacrifice, Rune begins to suspect the birds know more about the slayers - and the twins - than they're willing to admit. Nothing is more important to Shiv Crew than finding Levi and Denim, but when Lex psychically connects with the twins, it isn't good news she brings back. As always, COS is at the center of it all. The world is beginning to look at the church differently, thanks to the tireless work of Bill Rice and others like him. The humans' acceptance is turning to fear. And what people fear, they hate. What the slayers are planning next will either finish them for good or give them everything they've ever wanted - Karin Love and unchallenged power. Rune and the crew race against time to save River County from the biggest monster they've faced yet. If they fail, the church will be closer than ever to their dream of creating an Otherless world. In Obsidian Wings, Rune hides a devastating physical weakness, makes an important choice in her love life, and gains a new understanding that will help her face the future. No matter what happens, their world is changing. The crew is growing. And so is Rune Alexander.