A Tap On the Window by Linwood Barclay

Ages 14+

Cal Weaver is in his car on a rainy night when a young girl taps on his window, asking for a ride home. He is about to ignore her when he realizes that she is one of his son’s classmates. He isn’t prepared for what is about to happen next, however. She asks him to pull into a nearby restaurant so she can throw up, sick from too much underage drinking. When she comes back, however, Cal realizes that it isn’t her, but a girl that has switched places with her. Now he has gone from a guy who was trying to get a girl home safely to a suspect in the case of a missing girl.