The Silver Chair

In The Silver Chair, Eustace Scrubb returns to Narnia with his schoolmate Jill Pole only to find his friend King Caspian an old man. Caspian's dying wish is to find his son, Prince Rilian who has been kidnapped by an evil witch. With the help of Aslan and a Marsh-wiggle named Puddleglum, Eustace and Jill embark on a harrowing quest to find Rilian that takes them on a journey through the city of giants and the Underworld. The fourth book of the Chronicles of Narnia, it was first published in 1953.