13-Year-old sleuth Skylar Robbins is always on the lookout for a new mystery. When faced with a variety of creepy doors to explore, which one would she walk through first, looking for clues to her next case? Leave a comment describing what you think might be hiding behind one of these doors, and you will be in the running for a signed copy of the new Skylar Robbins paperback: The Mystery of the Missing Heiress!