The "Princess in Black" is a children's book series written by Shannon Hale and Dean Hale. It follows the adventures of a young princess named Magnolia who secretly becomes a superhero when danger arises in her kingdom. She dons a black mask and cape to fight off monsters and protect her realm. The series combines elements of fantasy and humor, making it appealing to young readers. Each book features engaging illustrations by LeUyen Pham that complement the story. The themes of bravery, friendship, and the balance between royal duties and personal passions are central to the narrative.