Shasta is the son of the poor fisherman Arsheesh in southern Calormen during the reign of the High King Peter in Narnia. When a great Lord of Calormen, the Tarkaan Anradin, stays the night in Arsheesh's hut, Shasta discovers that he is not really the son of the fisherman at all. When Arsheesh decides to sell Shasta for a slave, Shasta runs away with Bree, the Tarkaan's Talking Horse, on a journey to reach the free land of Narnia. On their way they meet the Tarkheena Aravis, a girl of noble Calormene blood who is running away from her father and the man to whom she had been betrothed against her will. Together they journey to Narnia, and in the capital city of Tashbaan discover that Prince Rabadash of Calormen is planning to invade Archenland and then Narnia. Shasta must warn the king of Archenland before it's too late . . . .