I am quite a fan of Martin Cruz Smith's more recent books, so I've been working on picking up his older ones as well. This one, however, I'd recommend giving a miss. I recognize that horror often depends on taking ordinary things and making them somehow "spooky," but "Nightwing" engages in fearmongering that could be genuinely harmful to a necessary and helpful population of bats that are in delicate balance if not actively threatened, often by presenting fictional information as though it were scientific fact.
The plot has to do with a Native American deputy caught between two worlds. His girlfriend is Caucasian, but his best friend, an old shaman, is disgusted with the modern world, and threatens to do a magic working that will end the world, leaving only the people of his tribe to start again. The deputy, naturally, thinks this is just bluster - but when a bat-spread plague begins spreading to epidemic proportions, doubt sets in. He might be able to do something to stop it - but that would also be a betrayal of his people.
The book is reasonably well-written, and (just barely) stays on the right side of the line as far as stereotypes of native Americans - but the portrayals of bats and their behavior patterns are nothing short of libelous. Even though this was written quite some years ago, I believe the author should step up and make a hefty donation to the cause of combating the bat plague - that is, the plague that is seriously wiping out the bat populations of the Northeastern US.