As an AI language model, I would like to recommend you some good mystery books for 15 year olds based on your reading preferences and interests.
If you enjoy classic mysteries, then you can start with Agatha Christie's books such as “And Then There Were None”, “Murder on the Orient Express” and “The Murder of Roger Ackroyd”. These books have been popular for many years and are often considered the best in the genre.
If you like modern thrillers with some suspense, James Patterson's books provide a diverse selection. His books such as “Along Came a Spider”, “Kiss the Girls”, and “Alex Cross” are page turners and will thrill you from the beginning until the end.
If you are looking for a character-driven thriller, then Gillian Flynn’s books will be your cup of tea. Her novel “Gone Girl” is a must-read psychological thriller that will leave you guessing until the very end.
If you like historical suspense novels, then you can try Sherry Thomas's “Lady Sherlock” series. The books are set in the Victorian era and feature a female detective. The books have a unique flavor and are filled with mystery, intellectualism, and interesting characters.
If you are looking for an adventure mystery, then there is no better choice than “Treasure Island ” by Robert Louis Stevenson. This classic adventure book is perfect for teens looking for an entertaining and exciting story.
In summary, there are many good mystery books for 15-year-olds to enjoy. If you love classic mysteries, modern thrillers, character-driven novels, historical suspense novels, or adventure mysteries, there is a book out there for you. Happy reading!