Penny Parker is hot on the trail of thieves that are hitting the airplane factory. Brass is disappearing, and all signs point to Sally Barker as the perpetrator. But is she? Or was she framed? Follow Penny as she investigates the Guilt of the Brass Thieves This book is from the Penny Parker series by Mildred A. Wirt, also known as ghostwriter Carolyn Keene, of the Nancy Drew series of books.