Borderline takes place along the Texas/Mexican border in Big Bend National Park. Anna is on administrative leave due to post traumatic stress disorder. She and her husband decide to take a raft trip that turns out to be anything but relaxing. As you can guess, this book deals with the issues of the many people who try to cross the border from Mexico to the US without permission. I really enjoyed this book. I found it to be one of Nevada Barr’s best.