Eleven-year-old Naomi loves all things outdoors--birds and beetles, bats and bunnies--in theory. She explores nature in the best possible way: the cold, hard facts in books. So when her parents' announcement of their impending divorce comes hand in hand with sending Naomi and her younger twin brothers to summer camp while they figure things out, it's salt in the wound for Naomi and her avoidance of hands-on experience.

Camp Twisted Pine could be worse. The counselors are nice, and Naomi likes her cabinmates, especially Jackie, whose blunt personality and frank dislike of the camp draw Naomi in quickly. Jackie is also hard of hearing and uses a hearing aid, and the girls quickly develop a routine of sign language lessons in their free time, which Naomi sees as a welcome break when all the s'mores-making and nature walks get to be a bit much.

But the campers aren't the only ones who roam the grounds of Camp Twisted Pine. When people start to go missing, including Jackie, Naomi has to find a way to save everyone--and herself. Her practical knowledge of the outdoors may still be rudimentary at best, but she has years of studying and the scientific method to fall back on. Can Naomi identify and stop the dangerous predator before it's too late?