The Only One Left — Pamela Beason

What does a human finger bone found by a signing gorilla have to do with Detective Matthew Finn's case of two missing girls? Maybe nothing. Maybe everything.
Memorial Day starts off strangely when a signing gorilla hands Detective Matthew Finn a human finger bone, and then explains the bone's origin with the mysterious clues of up, bird, and Snow, a favorite white cat. Finn's day gets far worse when his small police department in Evansburg, Washington, loans him to the adjacent county to investigate the case of two missing teenage girls. Adding to the chaos, an arsonist is torching abandoned buildings in the area, and Finn soon discovers a troubling history of young women who have vanished in the rural area. Frantic parents and demanding reporters are breathing down his neck. Can Finn fit the puzzle pieces together in time to save the girls?