"Prince Caspian" is the second book in C.S. Lewis's series, "The Chronicles of Narnia." It follows the Pevensie siblings—Peter, Susan, Edmund, and Lucy—as they return to the magical land of Narnia to help Prince Caspian reclaim his rightful throne from his usurping uncle, King Miraz. The story explores themes of bravery, loyalty, and the struggle between good and evil. As the Pevensies join forces with Caspian and the loyal creatures of Narnia, they face challenges that test their courage and unity, ultimately leading to a climactic battle for the future of the kingdom.