At the end of the 19th century, who would want to conquer the Sahara, a vast and hellish desert? France did, and this is the story of the two fanatical adventurers who made it possible. It is a dark and strange tale of survival in a harsh environment, extreme religious zeal, imperial dreams and violent death. This is a vivid, haunting and sharply witty history of a forgotten episode in Europe's colonial crusade, a narrative of self-sacrifice and cruelty, hatred and friendship, discovery and delusion, set against a backdrop of oceans of burning sand and waterless mountains of black rock.