Promise me
(Book)

Entertainment agent Myron Bolitar, determined to keep his friends' children safe in their last pressure-cooker months of high school, makes two neighborhood girls promise that if they are ever in a bind and afraid to call their parents, they will call him. A few nights later, one of the girls does call, and he takes her to where she says her friend lives. When the girl is reported missing the next day, and her parents learn that Myron was the last person to see her, he must race to find her before she is gone forever.