The Assignment by Jim Crawford

Detective Kevin Winters is emotionally involved when his girlfriend disappears without a trace. Working in his spare time to solve the case, his investigation is going nowhere until a similar kidnapping leads him to a self proclaimed psychic, four remarkable teenagers and a mysterious book. The four teenagers are given a reading assignment by their teacher. He tells them the best way to read a book is to get involved by pretending to be one of the characters. Unbeknownst to the four, they all start reading the same book and, per their teacher's instructions, assume one of the characters. The children finally realize the similarities between the book and their lives but obstacles surface when they attempt to convince the adults. When Kevin interviews the children and their families, he senses their unbelievable story might be true. In desperation and without telling his superiors, he digs deeper into their story. Will the path lead him to his girlfriend or is it an elaborate hoax?