When Lucy and Edmund Pevensie, along with their cousin Eustace, are swallowed into a painting and transported back to Narnia, they join King Caspian and a noble mouse named Reepicheep aboard the magnificent ship the Dawn Treader. The courageous voyagers travel to mysterious islands, confront mystical creatures, and reunite with the Great Lion Aslan and a mission that will determine the fate of Narnia itself!