Hidden Letters is the real life story of an eighteen-year-old Jewish Dutch boy. The book is based on the 86 letters, postcards, and a telegram he sent to his family in Amsterdam while he was imprisoned in a Nazi labor camp in Holland. Philip Flip Slier s letters, written in 1942, were discovered in 1997. His letters are supported with hundreds of other primary source documents, photographs, and maps that situate this young man s experience in the context of World War II. Flip s poignant writing shows the human side of war and reminds readers of the horrors of persecution and genocide. Middle and high school history and English teachers, in particular, will welcome this title into their curricula.