Kella, a young princess, and her elder sister are forced to leave their home because of war. They travel through the Sahara in a small caravan led by a mysterious traveller, who is to guide them to the prosperous Lake City in the Hoggar Mountains so they can start a new life. They find a city enclosed in a giant iron sphere and ruled by an oppressive organisation called the Committee, which was brought to power by a revolution seeking to free the city's people from dictatorship. Instead, the Committee has come to represent a new source of terror for the citizens. Here, Kella meets Afra, who is involved in a plot to overthrow the Committee. Her attraction to Afra and her shocked reaction to the Committee’s brutal rule spark Kella’s transformation from spoiled girl to revolutionary. She sets out on a new journey to build a culture based on freedom, honour and loyalty – and to become the Queen of the Hoggar.