Once again, Nancy faces two puzzling mysteries at once! The first concerns a valuable collection of rare books that Mrs. Horace Merriam commissioned anart dealer to sell-has he swindled her instead? The second mystery revolves around the baffling theft of a beautiful marble statue. To solve both mysteries, the famous young detective disguises herself and assumes a false identity. Despite these precautions, danger stalks Nancy's every move. An attempted kidnapping, a nearly disastrous sailboat c