The third book in C.S. Lewis' Chronicles of Narnia series, The Voyage of the Dawn Treader tells the story of Prince Caspian's quest to discover the seven lost lords of Narnia. The seven lords had disappeared among the many islands when Caspian's wicked Uncle Miraz ruled Narnia. The main goal of the voyage is for Caspian to fulfill his oath by finding the Lords of Narnia.
Other characters have invested interest in the journey as well. Reepicheep, the brave mouse, wants to sail as far east as possible where the "waters are sweet" to discovers Aslan's country.
The points of the voyage are (1) for Eustace, to discover his real self, (2) for Reepicheep, to go and stay in Aslan's country, (3) for Caspian, to find the 7 lords or to find out their deaths.